From 9cb66ef818f6598eb779f931e201a8d38e86a484 Mon Sep 17 00:00:00 2001
From: Manos Pitsidianakis <el13635@mail.ntua.gr>
Date: Thu, 25 Aug 2022 15:17:18 +0300
Subject: [PATCH] Fix all clippy warnings in `meli` crate

---
 config_macros.rs                              |   4 +-
 src/bin.rs                                    |  38 +--
 src/command.rs                                |  14 +-
 src/components/contacts.rs                    |  54 ++--
 src/components/contacts/contact_list.rs       |  10 +-
 src/components/mail/compose.rs                | 113 +++-----
 .../mail/compose/edit_attachments.rs          |   6 +-
 src/components/mail/compose/gpg.rs            |  14 +-
 src/components/mail/listing.rs                |  55 ++--
 src/components/mail/listing/compact.rs        |  25 +-
 src/components/mail/listing/conversations.rs  |  19 +-
 src/components/mail/listing/offline.rs        |   8 +-
 src/components/mail/listing/plain.rs          |  13 +-
 src/components/mail/listing/thread.rs         |  13 +-
 src/components/mail/pgp.rs                    |   2 +-
 src/components/mail/status.rs                 |   6 +-
 src/components/mail/view.rs                   | 266 ++++++++----------
 src/components/mail/view/envelope.rs          | 206 +++++++-------
 src/components/mail/view/thread.rs            |  41 +--
 src/components/notifications.rs               |   9 +-
 src/components/utilities.rs                   |  31 +-
 src/components/utilities/dialogs.rs           |   6 +-
 src/components/utilities/pager.rs             |  18 +-
 src/components/utilities/widgets.rs           |  12 +-
 src/conf.rs                                   |  23 +-
 src/conf/accounts.rs                          | 104 +++----
 src/conf/overrides.rs                         |   4 +-
 src/conf/shortcuts.rs                         |  17 +-
 src/conf/tags.rs                              |  11 +-
 src/conf/themes.rs                            | 172 +++++------
 src/mailcap.rs                                |  36 +--
 src/sqlite3.rs                                |  40 ++-
 src/state.rs                                  |  73 ++---
 src/terminal/cells.rs                         |  12 +-
 src/terminal/color.rs                         |  15 +-
 src/terminal/embed/grid.rs                    |  52 ++--
 src/terminal/keys.rs                          |  16 +-
 src/types.rs                                  |   8 +-
 src/types/helpers.rs                          |   3 +-
 39 files changed, 688 insertions(+), 881 deletions(-)

diff --git a/config_macros.rs b/config_macros.rs
index e4c3ca5c..1c8e40c3 100644
--- a/config_macros.rs
+++ b/config_macros.rs
@@ -50,7 +50,9 @@ pub fn override_derive(filenames: &[(&str, &str)]) {
  * along with meli. If not, see <http://www.gnu.org/licenses/>.
  */
 
-//! This module is automatically generated by build.rs.
+#![allow(clippy::derivable_impls)]
+
+//! This module is automatically generated by config_macros.rs.
 use super::*;
 
 "##
diff --git a/src/bin.rs b/src/bin.rs
index e1c627b5..510a5908 100644
--- a/src/bin.rs
+++ b/src/bin.rs
@@ -42,6 +42,8 @@ extern crate serde_json;
 extern crate smallvec;
 extern crate termion;
 
+use structopt::StructOpt;
+
 #[global_allocator]
 static GLOBAL: System = System;
 
@@ -120,6 +122,7 @@ fn notify(
     Ok(r)
 }
 
+#[cfg(feature = "cli-docs")]
 fn parse_manpage(src: &str) -> Result<ManPages> {
     match src {
         "" | "meli" | "main" => Ok(ManPages::Main),
@@ -132,8 +135,7 @@ fn parse_manpage(src: &str) -> Result<ManPages> {
     }
 }
 
-use structopt::StructOpt;
-
+#[cfg(feature = "cli-docs")]
 #[derive(Copy, Clone, Debug)]
 /// Choose manpage
 enum ManPages {
@@ -193,9 +195,11 @@ enum SubCommand {
 #[derive(Debug, StructOpt)]
 struct ManOpt {
     #[structopt(default_value = "meli", possible_values=&["meli", "conf", "themes"], value_name="PAGE", parse(try_from_str = parse_manpage))]
+    #[cfg(feature = "cli-docs")]
     page: ManPages,
     /// If true, output text in stdout instead of spawning $PAGER.
     #[structopt(long = "no-raw", alias = "no-raw", value_name = "bool")]
+    #[cfg(feature = "cli-docs")]
     no_raw: Option<Option<bool>>,
 }
 
@@ -243,7 +247,7 @@ fn run_app(opt: Opt) -> Result<()> {
         #[cfg(feature = "cli-docs")]
         Some(SubCommand::Man(manopt)) => {
             let ManOpt { page, no_raw } = manopt;
-            const MANPAGES: [&'static [u8]; 3] = [
+            const MANPAGES: [&[u8]; 3] = [
                 include_bytes!(concat!(env!("OUT_DIR"), "/meli.txt.gz")),
                 include_bytes!(concat!(env!("OUT_DIR"), "/meli.conf.txt.gz")),
                 include_bytes!(concat!(env!("OUT_DIR"), "/meli-themes.txt.gz")),
@@ -255,10 +259,9 @@ fn run_app(opt: Opt) -> Result<()> {
                 str::parse::<usize>(unsafe {
                     std::str::from_utf8_unchecked(gz.header().unwrap().comment().unwrap())
                 })
-                .expect(&format!(
-                    "{:?} was not compressed with size comment header",
-                    page
-                )),
+                .unwrap_or_else(|_| {
+                    panic!("{:?} was not compressed with size comment header", page)
+                }),
             );
             gz.read_to_string(&mut v)?;
 
@@ -271,19 +274,18 @@ fn run_app(opt: Opt) -> Result<()> {
                         return Ok(());
                     }
                 }
-            } else {
-                if unsafe { libc::isatty(libc::STDOUT_FILENO) != 1 } {
-                    println!("{}", &v);
-                    return Ok(());
-                }
+            } else if unsafe { libc::isatty(libc::STDOUT_FILENO) != 1 } {
+                println!("{}", &v);
+                return Ok(());
             }
 
             use std::process::{Command, Stdio};
-            let mut handle = Command::new(std::env::var("PAGER").unwrap_or("more".to_string()))
-                .stdin(Stdio::piped())
-                .stdout(Stdio::inherit())
-                .stderr(Stdio::inherit())
-                .spawn()?;
+            let mut handle =
+                Command::new(std::env::var("PAGER").unwrap_or_else(|_| "more".to_string()))
+                    .stdin(Stdio::piped())
+                    .stdout(Stdio::inherit())
+                    .stderr(Stdio::inherit())
+                    .spawn()?;
             handle.stdin.take().unwrap().write_all(v.as_bytes())?;
             handle.wait()?;
 
@@ -314,7 +316,7 @@ fn run_app(opt: Opt) -> Result<()> {
         }
         Some(SubCommand::PrintLoadedThemes) => {
             let s = conf::FileSettings::new()?;
-            print!("{}", s.terminal.themes.to_string());
+            print!("{}", s.terminal.themes);
             return Ok(());
         }
         Some(SubCommand::PrintDefaultTheme) => {
diff --git a/src/command.rs b/src/command.rs
index 8f8cede5..f219641c 100644
--- a/src/command.rs
+++ b/src/command.rs
@@ -116,7 +116,7 @@ impl TokenStream {
             }
             *s = &s[ptr..];
             //println!("\t before s.is_empty() {:?} {:?}", t, s);
-            if s.is_empty() || &*s == &" " {
+            if s.is_empty() || *s == " " {
                 match t.inner() {
                     Literal(lit) => {
                         sugg.insert(format!("{}{}", if s.is_empty() { " " } else { "" }, lit));
@@ -126,7 +126,7 @@ impl TokenStream {
                             //println!("adding empty suggestions for {:?}", t);
                             let mut _s = *s;
                             let mut m = t.matches(&mut _s, sugg);
-                            tokens.extend(m.drain(..));
+                            tokens.append(&mut m);
                         }
                     }
                     Seq(_s) => {}
@@ -167,7 +167,7 @@ impl TokenStream {
                         let mut _s = *s;
                         let mut m = t.matches(&mut _s, sugg);
                         if !m.is_empty() {
-                            tokens.extend(m.drain(..));
+                            tokens.append(&mut m);
                             //println!("_s is empty {}", _s.is_empty());
                             cont = !_s.is_empty();
                             *s = _s;
@@ -262,7 +262,7 @@ define_commands!([
                    desc: "set [seen/unseen], toggles message's Seen flag.",
                    tokens: &[One(Literal("set")), One(Alternatives(&[to_stream!(One(Literal("seen"))), to_stream!(One(Literal("unseen")))]))],
                    parser: (
-                       fn seen_flag<'a>(input: &'a [u8]) -> IResult<&'a [u8], Action> {
+                       fn seen_flag(input: &'_ [u8]) -> IResult<&'_ [u8], Action> {
                            let (input, _) = tag("set")(input.trim())?;
                            let (input, _) = is_a(" ")(input)?;
                            let (input, ret) = alt((map(tag("seen"), |_| Listing(SetSeen)), map(tag("unseen"), |_| Listing(SetUnseen))))(input)?;
@@ -275,7 +275,7 @@ define_commands!([
                    desc: "delete message",
                    tokens: &[One(Literal("delete"))],
                    parser: (
-                       fn delete_message<'a>(input: &'a [u8]) -> IResult<&'a [u8], Action> {
+                       fn delete_message(input: &'_ [u8]) -> IResult<&'_ [u8], Action> {
                            let (input, ret) = map(preceded(tag("delete"), eof), |_| Listing(Delete))(input)?;
                            let (input, _) = eof(input)?;
                            Ok((input, ret))
@@ -536,7 +536,7 @@ define_commands!([
                   desc: "filter EXECUTABLE ARGS",
                   tokens: &[One(Literal("filter")), One(Filepath), ZeroOrMore(QuotedStringValue)],
                   parser:(
-                      fn filter<'a>(input: &'a [u8]) -> IResult<&'a [u8], Action> {
+                      fn filter(input: &'_ [u8]) -> IResult<&'_ [u8], Action> {
                           let (input, _) = tag("filter")(input.trim())?;
                           let (input, _) = is_a(" ")(input)?;
                           let (input, cmd) = map_res(not_line_ending, std::str::from_utf8)(input)?;
@@ -1080,7 +1080,7 @@ pub fn command_completion_suggestions(input: &str) -> Vec<String> {
         }
         if let Some((s, Filepath)) = _m.last() {
             let p = std::path::Path::new(s);
-            sugg.extend(p.complete(true).into_iter().map(|m| m.into()));
+            sugg.extend(p.complete(true).into_iter());
         }
     }
     sugg.into_iter()
diff --git a/src/components/contacts.rs b/src/components/contacts.rs
index ef00c85f..e72ab3f2 100644
--- a/src/components/contacts.rs
+++ b/src/components/contacts.rs
@@ -29,7 +29,7 @@ pub use self::contact_list::*;
 #[derive(Debug)]
 enum ViewMode {
     ReadOnly,
-    Discard(UIDialog<char>),
+    Discard(Box<UIDialog<char>>),
     Edit,
     //New,
 }
@@ -113,27 +113,21 @@ impl ContactManager {
         self.form = FormWidget::new(("Save".into(), true));
         self.form.add_button(("Cancel(Esc)".into(), false));
         self.form
-            .push(("NAME".into(), self.card.name().to_string().into()));
+            .push(("NAME".into(), self.card.name().to_string()));
         self.form.push((
             "ADDITIONAL NAME".into(),
-            self.card.additionalname().to_string().into(),
-        ));
-        self.form.push((
-            "NAME PREFIX".into(),
-            self.card.name_prefix().to_string().into(),
-        ));
-        self.form.push((
-            "NAME SUFFIX".into(),
-            self.card.name_suffix().to_string().into(),
+            self.card.additionalname().to_string(),
         ));
         self.form
-            .push(("E-MAIL".into(), self.card.email().to_string().into()));
+            .push(("NAME PREFIX".into(), self.card.name_prefix().to_string()));
         self.form
-            .push(("URL".into(), self.card.url().to_string().into()));
+            .push(("NAME SUFFIX".into(), self.card.name_suffix().to_string()));
         self.form
-            .push(("KEY".into(), self.card.key().to_string().into()));
+            .push(("E-MAIL".into(), self.card.email().to_string()));
+        self.form.push(("URL".into(), self.card.url().to_string()));
+        self.form.push(("KEY".into(), self.card.key().to_string()));
         for (k, v) in self.card.extra_properties() {
-            self.form.push((k.to_string().into(), v.to_string().into()));
+            self.form.push((k.to_string().into(), v.to_string()));
         }
     }
 
@@ -168,26 +162,20 @@ impl Component for ContactManager {
             (set_y(upper_left, get_y(upper_left) + 2), bottom_right),
             context,
         );
-        match self.mode {
-            ViewMode::Discard(ref mut selector) => {
-                /* Let user choose whether to quit with/without saving or cancel */
-                selector.draw(grid, area, context);
-            }
-            _ => {}
+        if let ViewMode::Discard(ref mut selector) = self.mode {
+            /* Let user choose whether to quit with/without saving or cancel */
+            selector.draw(grid, area, context);
         }
 
         context.dirty_areas.push_back(area);
     }
 
     fn process_event(&mut self, event: &mut UIEvent, context: &mut Context) -> bool {
-        match event {
-            UIEvent::ConfigReload { old_settings: _ } => {
-                self.theme_default = crate::conf::value(context, "theme_default");
-                self.content = CellBuffer::new_with_context(100, 1, None, context);
-                self.initialized = false;
-                self.set_dirty(true);
-            }
-            _ => {}
+        if let UIEvent::ConfigReload { old_settings: _ } = event {
+            self.theme_default = crate::conf::value(context, "theme_default");
+            self.content = CellBuffer::new_with_context(100, 1, None, context);
+            self.initialized = false;
+            self.set_dirty(true);
         }
         match self.mode {
             ViewMode::Discard(ref mut selector) => {
@@ -209,9 +197,7 @@ impl Component for ContactManager {
                     match self.form.buttons_result() {
                         None => {}
                         Some(true) => {
-                            let fields = std::mem::replace(&mut self.form, FormWidget::default())
-                                .collect()
-                                .unwrap();
+                            let fields = std::mem::take(&mut self.form).collect().unwrap();
                             let fields: HashMap<String, String> = fields
                                 .into_iter()
                                 .map(|(s, v)| {
@@ -290,7 +276,7 @@ impl Component for ContactManager {
 
         let parent_id = self.parent_id;
         /* Play it safe and ask user for confirmation */
-        self.mode = ViewMode::Discard(UIDialog::new(
+        self.mode = ViewMode::Discard(Box::new(UIDialog::new(
             "this contact has unsaved changes",
             vec![
                 ('x', "quit without saving".to_string()),
@@ -305,7 +291,7 @@ impl Component for ContactManager {
                 _ => None,
             })),
             context,
-        ));
+        )));
         self.set_dirty(true);
         false
     }
diff --git a/src/components/contacts/contact_list.rs b/src/components/contacts/contact_list.rs
index 38fe87f2..b240c9fd 100644
--- a/src/components/contacts/contact_list.rs
+++ b/src/components/contacts/contact_list.rs
@@ -34,7 +34,7 @@ enum ViewMode {
 #[derive(Debug)]
 struct AccountMenuEntry {
     name: String,
-    hash: AccountHash,
+    _hash: AccountHash,
     // Index in the config account vector.
     index: usize,
 }
@@ -82,7 +82,7 @@ impl ContactList {
             .enumerate()
             .map(|(i, (h, a))| AccountMenuEntry {
                 name: a.name().to_string(),
-                hash: *h,
+                _hash: *h,
                 index: i,
             })
             .collect();
@@ -216,7 +216,6 @@ impl ContactList {
                 ((0, 0), (message.len() - 1, 0)),
                 None,
             );
-            return;
         }
     }
 
@@ -241,7 +240,7 @@ impl ContactList {
         self.dirty = false;
         let mut y = get_y(upper_left);
         for a in &self.accounts {
-            self.print_account(grid, (set_y(upper_left, y), bottom_right), &a, context);
+            self.print_account(grid, (set_y(upper_left, y), bottom_right), a, context);
             y += 1;
         }
 
@@ -393,6 +392,7 @@ impl ContactList {
                     }
                 }
                 PageMovement::PageDown(multiplier) => {
+                    #[allow(clippy::comparison_chain)]
                     if self.new_cursor_pos + rows * multiplier < self.length {
                         self.new_cursor_pos += rows * multiplier;
                     } else if self.new_cursor_pos + rows * multiplier > self.length {
@@ -782,7 +782,7 @@ impl Component for ContactList {
                         .push_back(UIEvent::StatusEvent(StatusEvent::BufClear));
                     return true;
                 }
-                UIEvent::Input(Key::Char(c)) if c >= '0' && c <= '9' => {
+                UIEvent::Input(Key::Char(c)) if ('0'..='9').contains(&c) => {
                     self.cmd_buf.push(c);
                     context
                         .replies
diff --git a/src/components/mail/compose.rs b/src/components/mail/compose.rs
index 605231af..217f5fe4 100644
--- a/src/components/mail/compose.rs
+++ b/src/components/mail/compose.rs
@@ -116,19 +116,11 @@ enum ViewMode {
 
 impl ViewMode {
     fn is_edit(&self) -> bool {
-        if let ViewMode::Edit = self {
-            true
-        } else {
-            false
-        }
+        matches!(self, ViewMode::Edit)
     }
 
     fn is_edit_attachments(&self) -> bool {
-        if let ViewMode::EditAttachments { .. } = self {
-            true
-        } else {
-            false
-        }
+        matches!(self, ViewMode::EditAttachments { .. })
     }
 }
 
@@ -160,7 +152,7 @@ impl Composer {
             form: FormWidget::default(),
             mode: ViewMode::Edit,
             #[cfg(feature = "gpgme")]
-            gpg_state: gpg::GpgComposeState::new(),
+            gpg_state: gpg::GpgComposeState::default(),
             dirty: true,
             has_changes: false,
             embed_area: ((0, 0), (0, 0)),
@@ -249,11 +241,7 @@ impl Composer {
         ret.draft
             .set_header("In-Reply-To", envelope.message_id_display().into());
 
-        if let Some(reply_to) = envelope
-            .other_headers()
-            .get("To")
-            .and_then(|v| v.as_str().try_into().ok())
-        {
+        if let Some(reply_to) = envelope.other_headers().get("To").map(|v| v.as_str()) {
             let to: &str = reply_to;
             let extra_identities = &account.settings.account.extra_identities;
             if let Some(extra) = extra_identities
@@ -288,30 +276,26 @@ impl Composer {
                 .and_then(|v| v.as_str().try_into().ok())
             {
                 to.insert(reply_to);
+            } else if let Some(reply_to) = envelope
+                .other_headers()
+                .get("Reply-To")
+                .and_then(|v| v.as_str().try_into().ok())
+            {
+                to.insert(reply_to);
             } else {
-                if let Some(reply_to) = envelope
-                    .other_headers()
-                    .get("Reply-To")
-                    .and_then(|v| v.as_str().try_into().ok())
-                {
-                    to.insert(reply_to);
-                } else {
-                    to.extend(envelope.from().iter().cloned());
-                }
+                to.extend(envelope.from().iter().cloned());
             }
             to.extend(envelope.to().iter().cloned());
-            if let Some(ours) = TryInto::<Address>::try_into(
+            if let Ok(ours) = TryInto::<Address>::try_into(
                 crate::components::mail::get_display_name(context, coordinates.0).as_str(),
-            )
-            .ok()
-            {
+            ) {
                 to.remove(&ours);
             }
             ret.draft.set_header("To", {
                 let mut ret: String =
                     to.into_iter()
                         .fold(String::new(), |mut s: String, n: Address| {
-                            s.extend(n.to_string().chars());
+                            s.push_str(&n.to_string());
                             s.push_str(", ");
                             s
                         });
@@ -320,14 +304,12 @@ impl Composer {
                 ret
             });
             ret.draft.set_header("Cc", envelope.field_cc_to_string());
+        } else if let Some(reply_to) = envelope.other_headers().get("Mail-Reply-To") {
+            ret.draft.set_header("To", reply_to.to_string());
+        } else if let Some(reply_to) = envelope.other_headers().get("Reply-To") {
+            ret.draft.set_header("To", reply_to.to_string());
         } else {
-            if let Some(reply_to) = envelope.other_headers().get("Mail-Reply-To") {
-                ret.draft.set_header("To", reply_to.to_string());
-            } else if let Some(reply_to) = envelope.other_headers().get("Reply-To") {
-                ret.draft.set_header("To", reply_to.to_string());
-            } else {
-                ret.draft.set_header("To", envelope.field_from_to_string());
-            }
+            ret.draft.set_header("To", envelope.field_from_to_string());
         }
         ret.draft.body = {
             let mut ret = attribution_string(
@@ -481,7 +463,7 @@ To: {}
         let header_values = self.form.values_mut();
         let draft_header_map = self.draft.headers_mut();
         for (k, v) in draft_header_map.iter_mut() {
-            if let Some(ref vn) = header_values.get(k.as_str()) {
+            if let Some(vn) = header_values.get(k.as_str()) {
                 *v = vn.as_str().to_string();
             }
         }
@@ -498,23 +480,22 @@ To: {}
             if k == "To" || k == "Cc" || k == "Bcc" {
                 self.form.push_cl((
                     k.into(),
-                    headers[k].to_string().into(),
+                    headers[k].to_string(),
                     Box::new(move |c, term| {
                         let book: &AddressBook = &c.accounts[&account_hash].address_book;
                         let results: Vec<String> = book.search(term);
                         results
                             .into_iter()
-                            .map(|r| AutoCompleteEntry::from(r))
+                            .map(AutoCompleteEntry::from)
                             .collect::<Vec<AutoCompleteEntry>>()
                     }),
                 ));
             } else if k == "From" {
                 self.form.push_cl((
                     k.into(),
-                    headers[k].to_string().into(),
+                    headers[k].to_string(),
                     Box::new(move |c, _term| {
-                        let results: Vec<(String, String)> = c
-                            .accounts
+                        c.accounts
                             .values()
                             .map(|acc| {
                                 let addr = if let Some(display_name) =
@@ -548,15 +529,12 @@ To: {}
 
                                 (addr, desc)
                             })
-                            .collect::<Vec<_>>();
-                        results
-                            .into_iter()
-                            .map(|r| AutoCompleteEntry::from(r))
+                            .map(AutoCompleteEntry::from)
                             .collect::<Vec<AutoCompleteEntry>>()
                     }),
                 ));
             } else {
-                self.form.push((k.into(), headers[k].to_string().into()));
+                self.form.push((k.into(), headers[k].to_string()));
             }
         }
     }
@@ -858,7 +836,7 @@ impl Component for Composer {
                     clear_area(grid, embed_area, theme_default);
                     copy_area(
                         grid,
-                        &guard.grid.buffer(),
+                        guard.grid.buffer(),
                         embed_area,
                         ((0, 0), pos_dec(guard.grid.terminal_size, (1, 1))),
                     );
@@ -871,7 +849,7 @@ impl Component for Composer {
                     let guard = embed_pty.lock().unwrap();
                     copy_area(
                         grid,
-                        &guard.grid.buffer(),
+                        guard.grid.buffer(),
                         embed_area,
                         ((0, 0), pos_dec(guard.grid.terminal_size, (1, 1))),
                     );
@@ -1120,8 +1098,7 @@ impl Component for Composer {
                 UIEvent::FinishedUIDialog(id, ref mut result),
             ) if selector.id() == *id => {
                 if let Some(to_val) = result.downcast_mut::<String>() {
-                    self.draft
-                        .set_header("To", std::mem::replace(to_val, String::new()));
+                    self.draft.set_header("To", std::mem::take(to_val));
                     self.update_form();
                 }
                 self.mode = ViewMode::Edit;
@@ -1677,7 +1654,7 @@ impl Component for Composer {
                 log(
                     format!(
                         "Executing: sh -c \"{}\"",
-                        editor_command.replace("\"", "\\\"")
+                        editor_command.replace('"', "\\\"")
                     ),
                     DEBUG,
                 );
@@ -1804,9 +1781,10 @@ impl Component for Composer {
                     return true;
                 }
                 Action::Compose(ComposeAction::AddAttachmentFilePicker(ref command)) => {
-                    let command = if let Some(ref cmd) = command
-                        .as_ref()
-                        .or_else(|| context.settings.terminal.file_picker_command.as_ref())
+                    let command = if let Some(cmd) =
+                        command
+                            .as_ref()
+                            .or(context.settings.terminal.file_picker_command.as_ref())
                     {
                         cmd.as_str()
                     } else {
@@ -1823,7 +1801,7 @@ impl Component for Composer {
                     }
 
                     log(
-                        format!("Executing: sh -c \"{}\"", command.replace("\"", "\\\"")),
+                        format!("Executing: sh -c \"{}\"", command.replace('"', "\\\"")),
                         DEBUG,
                     );
                     match Command::new("sh")
@@ -1838,7 +1816,7 @@ impl Component for Composer {
                             debug!(&String::from_utf8_lossy(&stderr));
                             for path in stderr.split(|c| [b'\0', b'\t', b'\n'].contains(c)) {
                                 match melib::email::compose::attachment_from_file(
-                                    &String::from_utf8_lossy(&path).as_ref(),
+                                    &String::from_utf8_lossy(path).as_ref(),
                                 ) {
                                     Ok(a) => {
                                         self.draft.attachments_mut().push(a);
@@ -1848,7 +1826,7 @@ impl Component for Composer {
                                         context.replies.push_back(UIEvent::Notification(
                                             Some(format!(
                                                 "could not add attachment: {}",
-                                                String::from_utf8_lossy(&path)
+                                                String::from_utf8_lossy(path)
                                             )),
                                             err.to_string(),
                                             Some(NotificationType::Error(
@@ -1984,7 +1962,7 @@ impl Component for Composer {
                 Some(Box::new(move |id: ComponentId, results: &[char]| {
                     Some(UIEvent::FinishedUIDialog(
                         id,
-                        Box::new(results.get(0).map(|c| *c).unwrap_or('n')),
+                        Box::new(results.get(0).copied().unwrap_or('n')),
                     ))
                 })),
                 context,
@@ -2033,7 +2011,7 @@ impl Component for Composer {
                 Some(Box::new(move |id: ComponentId, results: &[char]| {
                     Some(UIEvent::FinishedUIDialog(
                         id,
-                        Box::new(results.get(0).map(|c| *c).unwrap_or('n')),
+                        Box::new(results.get(0).copied().unwrap_or('n')),
                     ))
                 })),
                 context,
@@ -2136,7 +2114,7 @@ pub fn send_draft(
             let body: AttachmentBuilder = Attachment::new(
                 content_type,
                 Default::default(),
-                std::mem::replace(&mut draft.body, String::new()).into_bytes(),
+                std::mem::take(&mut draft.body).into_bytes(),
             )
             .into();
             draft.attachments.insert(0, body);
@@ -2195,6 +2173,7 @@ pub fn send_draft_async(
     let format_flowed = *account_settings!(context[account_hash].composing.format_flowed);
     let event_sender = context.sender.clone();
     #[cfg(feature = "gpgme")]
+    #[allow(clippy::type_complexity)]
     let mut filters_stack: Vec<
         Box<
             dyn FnOnce(
@@ -2207,7 +2186,7 @@ pub fn send_draft_async(
     #[cfg(feature = "gpgme")]
     if gpg_state.sign_mail.is_true() && !gpg_state.encrypt_mail.is_true() {
         filters_stack.push(Box::new(crate::components::mail::pgp::sign_filter(
-            gpg_state.sign_keys.clone(),
+            gpg_state.sign_keys,
         )?));
     } else if gpg_state.encrypt_mail.is_true() {
         filters_stack.push(Box::new(crate::components::mail::pgp::encrypt_filter(
@@ -2216,7 +2195,7 @@ pub fn send_draft_async(
             } else {
                 None
             },
-            gpg_state.encrypt_keys.clone(),
+            gpg_state.encrypt_keys,
         )?));
     }
     let send_mail = account_settings!(context[account_hash].composing.send_mail).clone();
@@ -2233,11 +2212,11 @@ pub fn send_draft_async(
     let mut body: AttachmentBuilder = Attachment::new(
         content_type,
         Default::default(),
-        std::mem::replace(&mut draft.body, String::new()).into_bytes(),
+        std::mem::take(&mut draft.body).into_bytes(),
     )
     .into();
     if !draft.attachments.is_empty() {
-        let mut parts = std::mem::replace(&mut draft.attachments, Vec::new());
+        let mut parts = std::mem::take(&mut draft.attachments);
         parts.insert(0, body);
         let boundary = ContentType::make_boundary(&parts);
         body = Attachment::new(
@@ -2261,7 +2240,7 @@ pub fn send_draft_async(
         let message = Arc::new(draft.finalise()?);
         let ret = send_cb(message.clone()).await;
         let is_ok = ret.is_ok();
-        if !is_ok || (store_sent_mail && is_ok) {
+        if !is_ok || store_sent_mail {
             event_sender
                 .send(ThreadEvent::UIEvent(UIEvent::Callback(CallbackFn(
                     Box::new(move |context| {
diff --git a/src/components/mail/compose/edit_attachments.rs b/src/components/mail/compose/edit_attachments.rs
index 8acac898..54a625ea 100644
--- a/src/components/mail/compose/edit_attachments.rs
+++ b/src/components/mail/compose/edit_attachments.rs
@@ -37,7 +37,7 @@ impl Default for EditAttachmentCursor {
 pub enum EditAttachmentMode {
     Overview,
     Edit {
-        inner: FormWidget<FormButtonActions>,
+        inner: Box<FormWidget<FormButtonActions>>,
         no: usize,
     },
 }
@@ -68,7 +68,7 @@ impl EditAttachments {
 }
 
 impl EditAttachmentsRefMut<'_, '_> {
-    fn new_edit_widget(&self, no: usize) -> Option<FormWidget<FormButtonActions>> {
+    fn new_edit_widget(&self, no: usize) -> Option<Box<FormWidget<FormButtonActions>>> {
         if no >= self.draft.attachments().len() {
             return None;
         }
@@ -80,7 +80,7 @@ impl EditAttachmentsRefMut<'_, '_> {
         ret.add_button(("Cancel".into(), FormButtonActions::Cancel));
         ret.push(("Filename".into(), filename.unwrap_or_default().to_string()));
         ret.push(("Mime type".into(), mime_type.to_string()));
-        Some(ret)
+        Some(Box::new(ret))
     }
 }
 
diff --git a/src/components/mail/compose/gpg.rs b/src/components/mail/compose/gpg.rs
index 448a5bfe..eaba98f7 100644
--- a/src/components/mail/compose/gpg.rs
+++ b/src/components/mail/compose/gpg.rs
@@ -36,7 +36,7 @@ pub enum KeySelection {
         err: MeliError,
     },
     Loaded {
-        widget: UIDialog<melib::gpgme::Key>,
+        widget: Box<UIDialog<melib::gpgme::Key>>,
         keys: Vec<melib::gpgme::Key>,
     },
 }
@@ -129,7 +129,7 @@ impl Component for KeySelection {
                                     match Self::new(
                                         *secret,
                                         *local,
-                                        std::mem::replace(pattern, String::new()),
+                                        std::mem::take(pattern),
                                         *allow_remote_lookup,
                                         context,
                                     ) {
@@ -166,7 +166,7 @@ impl Component for KeySelection {
                                 }
                                 return false;
                             }
-                            let mut widget = UIDialog::new(
+                            let mut widget = Box::new(UIDialog::new(
                                 "select key",
                                 keys.iter()
                                     .map(|k| {
@@ -185,12 +185,12 @@ impl Component for KeySelection {
                                     move |id: ComponentId, results: &[melib::gpgme::Key]| {
                                         Some(UIEvent::FinishedUIDialog(
                                             id,
-                                            Box::new(results.get(0).map(|k| k.clone())),
+                                            Box::new(results.get(0).cloned()),
                                         ))
                                     },
                                 )),
                                 context,
-                            );
+                            ));
                             widget.set_dirty(true);
                             *self = KeySelection::Loaded { widget, keys };
                         }
@@ -275,8 +275,8 @@ pub struct GpgComposeState {
     pub sign_keys: Vec<melib::gpgme::Key>,
 }
 
-impl GpgComposeState {
-    pub fn new() -> Self {
+impl Default for GpgComposeState {
+    fn default() -> Self {
         GpgComposeState {
             sign_mail: ToggleFlag::Unset,
             encrypt_mail: ToggleFlag::Unset,
diff --git a/src/components/mail/listing.rs b/src/components/mail/listing.rs
index c9685672..c9f894d1 100644
--- a/src/components/mail/listing.rs
+++ b/src/components/mail/listing.rs
@@ -176,7 +176,6 @@ struct AccountMenuEntry {
     name: String,
     hash: AccountHash,
     index: usize,
-    visible: bool,
     entries: SmallVec<[MailboxMenuEntry; 16]>,
 }
 
@@ -380,7 +379,7 @@ pub trait MailListingTrait: ListingTrait {
                     .map(|&env_hash| account.operation(env_hash).and_then(|mut op| op.as_bytes()))
                     .collect::<Result<Vec<_>>>();
                 let path_ = path.to_path_buf();
-                let format = format.clone().unwrap_or_default();
+                let format = (*format).unwrap_or_default();
                 let collection = account.collection.clone();
                 let (sender, mut receiver) = crate::jobs::oneshot::channel();
                 let fut: Pin<Box<dyn Future<Output = Result<()>> + Send + 'static>> =
@@ -521,11 +520,11 @@ pub trait ListingTrait: Component {
 
 #[derive(Debug)]
 pub enum ListingComponent {
-    Plain(PlainListing),
-    Threaded(ThreadListing),
-    Compact(CompactListing),
-    Conversations(ConversationsListing),
-    Offline(OfflineListing),
+    Plain(Box<PlainListing>),
+    Threaded(Box<ThreadListing>),
+    Compact(Box<CompactListing>),
+    Conversations(Box<ConversationsListing>),
+    Offline(Box<OfflineListing>),
 }
 use crate::ListingComponent::*;
 
@@ -534,11 +533,11 @@ impl core::ops::Deref for ListingComponent {
 
     fn deref(&self) -> &Self::Target {
         match &self {
-            Compact(ref l) => l,
-            Plain(ref l) => l,
-            Threaded(ref l) => l,
-            Conversations(ref l) => l,
-            Offline(ref l) => l,
+            Compact(ref l) => l.as_ref(),
+            Plain(ref l) => l.as_ref(),
+            Threaded(ref l) => l.as_ref(),
+            Conversations(ref l) => l.as_ref(),
+            Offline(ref l) => l.as_ref(),
         }
     }
 }
@@ -546,11 +545,11 @@ impl core::ops::Deref for ListingComponent {
 impl core::ops::DerefMut for ListingComponent {
     fn deref_mut(&mut self) -> &mut (dyn MailListingTrait + 'static) {
         match self {
-            Compact(l) => l,
-            Plain(l) => l,
-            Threaded(l) => l,
-            Conversations(l) => l,
-            Offline(l) => l,
+            Compact(l) => l.as_mut(),
+            Plain(l) => l.as_mut(),
+            Threaded(l) => l.as_mut(),
+            Conversations(l) => l.as_mut(),
+            Offline(l) => l.as_mut(),
         }
     }
 }
@@ -611,7 +610,6 @@ pub struct Listing {
     accounts: Vec<AccountMenuEntry>,
     status: Option<AccountStatus>,
     dirty: bool,
-    visible: bool,
     cursor_pos: (usize, MenuEntryCursor),
     menu_cursor_pos: (usize, MenuEntryCursor),
     menu_content: CellBuffer,
@@ -755,12 +753,10 @@ impl Component for Listing {
                 }
                 return true;
             }
-            UIEvent::StartupCheck(ref f) => {
-                if self.component.coordinates().1 == *f {
-                    if !self.startup_checks_rate.tick() {
-                        return false;
-                    }
-                }
+            UIEvent::StartupCheck(ref f)
+                if self.component.coordinates().1 == *f && !self.startup_checks_rate.tick() =>
+            {
+                return false;
             }
             UIEvent::Timer(n) if *n == self.startup_checks_rate.id() => {
                 if self.startup_checks_rate.active {
@@ -1127,7 +1123,7 @@ impl Component for Listing {
                         Action::Listing(ListingAction::Import(file_path, mailbox_path)) => {
                             let account = &mut context.accounts[self.cursor_pos.0];
                             if let Err(err) = account
-                                .mailbox_by_path(&mailbox_path)
+                                .mailbox_by_path(mailbox_path)
                                 .and_then(|mailbox_hash| {
                                     Ok((
                                         std::fs::read(&file_path).chain_err_summary(|| {
@@ -1687,7 +1683,7 @@ impl Component for Listing {
                     .push_back(UIEvent::StatusEvent(StatusEvent::BufClear));
                 return true;
             }
-            UIEvent::Input(Key::Char(c)) if c >= '0' && c <= '9' => {
+            UIEvent::Input(Key::Char(c)) if ('0'..='9').contains(&c) => {
                 self.cmd_buf.push(c);
                 self.component.set_modifier_active(true);
                 context
@@ -1808,7 +1804,6 @@ impl Listing {
                     name: a.name().to_string(),
                     hash: *h,
                     index: i,
-                    visible: true,
                     entries,
                 }
             })
@@ -1818,7 +1813,6 @@ impl Listing {
             component: Offline(OfflineListing::new((first_account_hash, 0))),
             accounts: account_entries,
             status: None,
-            visible: true,
             dirty: true,
             cursor_pos: (0, MenuEntryCursor::Mailbox(0)),
             menu_cursor_pos: (0, MenuEntryCursor::Mailbox(0)),
@@ -1954,7 +1948,6 @@ impl Listing {
 
         #[derive(Copy, Debug, Clone)]
         struct Line {
-            visible: bool,
             collapsed: bool,
             depth: usize,
             inc: usize,
@@ -1990,7 +1983,7 @@ impl Listing {
                 indentation,
                 has_sibling,
                 mailbox_hash,
-                visible,
+                visible: _,
                 collapsed,
             },
         ) in self.accounts[aidx].entries.iter().enumerate()
@@ -1999,7 +1992,6 @@ impl Listing {
                 match context.accounts[self.accounts[aidx].index][&mailbox_hash].status {
                     crate::conf::accounts::MailboxStatus::Failed(_) => {
                         lines.push(Line {
-                            visible,
                             collapsed,
                             depth,
                             inc: i,
@@ -2012,7 +2004,6 @@ impl Listing {
                     }
                     _ => {
                         lines.push(Line {
-                            visible,
                             collapsed,
                             depth,
                             inc: i,
diff --git a/src/components/mail/listing/compact.rs b/src/components/mail/listing/compact.rs
index 955310c8..ab55248f 100644
--- a/src/components/mail/listing/compact.rs
+++ b/src/components/mail/listing/compact.rs
@@ -172,9 +172,12 @@ pub struct CompactListing {
     /// Cache current view.
     data_columns: DataColumns,
     rows_drawn: SegmentTree,
+    #[allow(clippy::type_complexity)]
     rows: Vec<((usize, (ThreadHash, EnvelopeHash)), EntryStrings)>,
 
+    #[allow(clippy::type_complexity)]
     search_job: Option<(String, JoinHandle<Result<SmallVec<[EnvelopeHash; 512]>>>)>,
+    #[allow(clippy::type_complexity)]
     select_job: Option<(String, JoinHandle<Result<SmallVec<[EnvelopeHash; 512]>>>)>,
     filter_term: String,
     filtered_selection: Vec<ThreadHash>,
@@ -220,7 +223,7 @@ impl MailListingTrait for CompactListing {
             .flatten()
             .chain(cursor_iter.into_iter().flatten())
             .cloned();
-        SmallVec::from_iter(iter.into_iter())
+        SmallVec::from_iter(iter)
     }
 
     /// Fill the `self.data_columns` `CellBuffers` with the contents of the account mailbox the user has
@@ -324,6 +327,7 @@ impl MailListingTrait for CompactListing {
         self.length = 0;
         let mut rows = Vec::with_capacity(1024);
         let mut min_width = (0, 0, 0, 0);
+        #[allow(clippy::type_complexity)]
         let mut row_widths: (
             SmallVec<[u8; 1024]>,
             SmallVec<[u8; 1024]>,
@@ -404,11 +408,7 @@ impl MailListingTrait for CompactListing {
             );
             /* subject */
             row_widths.3.push(
-                (entry_strings
-                    .flag
-                    .grapheme_width()
-                    .try_into()
-                    .unwrap_or(255)
+                (entry_strings.flag.grapheme_width()
                     + 1
                     + entry_strings.subject.grapheme_width()
                     + 1
@@ -876,8 +876,8 @@ impl fmt::Display for CompactListing {
 
 impl CompactListing {
     pub const DESCRIPTION: &'static str = "compact listing";
-    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Self {
-        CompactListing {
+    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Box<Self> {
+        Box::new(CompactListing {
             cursor_pos: (coordinates.0, 1, 0),
             new_cursor_pos: (coordinates.0, coordinates.1, 0),
             length: 0,
@@ -905,8 +905,9 @@ impl CompactListing {
             modifier_active: false,
             modifier_command: None,
             id: ComponentId::new_v4(),
-        }
+        })
     }
+
     fn make_entry_string(
         &self,
         e: &Envelope,
@@ -1423,7 +1424,7 @@ impl CompactListing {
             }
             /* Set fg color for flags */
             let mut x = 0;
-            if self.selection.get(&thread_hash).cloned().unwrap_or(false) {
+            if self.selection.get(thread_hash).cloned().unwrap_or(false) {
                 x += selected_flag_len;
             }
             if thread.snoozed() {
@@ -1887,7 +1888,7 @@ impl Component for CompactListing {
             UIEvent::EnvelopeRename(ref old_hash, ref new_hash) => {
                 let account = &context.accounts[&self.cursor_pos.0];
                 let threads = account.collection.get_threads(self.cursor_pos.1);
-                if !account.collection.contains_key(&new_hash) {
+                if !account.collection.contains_key(new_hash) {
                     return false;
                 }
                 let new_env_thread_node_hash = account.collection.get_env(*new_hash).thread();
@@ -1917,7 +1918,7 @@ impl Component for CompactListing {
             UIEvent::EnvelopeUpdate(ref env_hash) => {
                 let account = &context.accounts[&self.cursor_pos.0];
                 let threads = account.collection.get_threads(self.cursor_pos.1);
-                if !account.collection.contains_key(&env_hash) {
+                if !account.collection.contains_key(env_hash) {
                     return false;
                 }
                 let new_env_thread_node_hash = account.collection.get_env(*env_hash).thread();
diff --git a/src/components/mail/listing/conversations.rs b/src/components/mail/listing/conversations.rs
index f73c67d3..b29b4324 100644
--- a/src/components/mail/listing/conversations.rs
+++ b/src/components/mail/listing/conversations.rs
@@ -101,8 +101,10 @@ pub struct ConversationsListing {
     subsort: (SortField, SortOrder),
     all_threads: HashSet<ThreadHash>,
     order: HashMap<ThreadHash, usize>,
+    #[allow(clippy::type_complexity)]
     rows: std::result::Result<Vec<((usize, (ThreadHash, EnvelopeHash)), EntryStrings)>, String>,
 
+    #[allow(clippy::type_complexity)]
     search_job: Option<(String, JoinHandle<Result<SmallVec<[EnvelopeHash; 512]>>>)>,
     filter_term: String,
     filtered_selection: Vec<ThreadHash>,
@@ -148,7 +150,7 @@ impl MailListingTrait for ConversationsListing {
             .flatten()
             .chain(cursor_iter.into_iter().flatten())
             .cloned();
-        SmallVec::from_iter(iter.into_iter())
+        SmallVec::from_iter(iter)
     }
 
     fn refresh_mailbox(&mut self, context: &mut Context, force: bool) {
@@ -376,7 +378,7 @@ impl ListingTrait for ConversationsListing {
         if let Err(message) = self.rows.as_ref() {
             clear_area(grid, area, self.color_cache.theme_default);
             write_string_to_grid(
-                &message,
+                message,
                 grid,
                 self.color_cache.theme_default.fg,
                 self.color_cache.theme_default.bg,
@@ -584,8 +586,8 @@ impl ConversationsListing {
     const DESCRIPTION: &'static str = "conversations listing";
     //const PADDING_CHAR: char = ' '; //░';
 
-    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Self {
-        ConversationsListing {
+    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Box<Self> {
+        Box::new(ConversationsListing {
             cursor_pos: (coordinates.0, 1, 0),
             new_cursor_pos: (coordinates.0, coordinates.1, 0),
             length: 0,
@@ -609,7 +611,7 @@ impl ConversationsListing {
             modifier_active: false,
             modifier_command: None,
             id: ComponentId::new_v4(),
-        }
+        })
     }
 
     pub(super) fn make_entry_string(
@@ -714,8 +716,7 @@ impl ConversationsListing {
                     .settings
                     .listing
                     .datetime_fmt
-                    .as_ref()
-                    .map(String::as_str)
+                    .as_deref()
                     .or(Some("%Y-%m-%d %T")),
                 false,
             ),
@@ -1226,7 +1227,7 @@ impl Component for ConversationsListing {
                 UIEvent::EnvelopeRename(ref old_hash, ref new_hash) => {
                     let account = &context.accounts[&self.cursor_pos.0];
                     let threads = account.collection.get_threads(self.cursor_pos.1);
-                    if !account.collection.contains_key(&new_hash) {
+                    if !account.collection.contains_key(new_hash) {
                         return false;
                     }
                     let env_thread_node_hash = account.collection.get_env(*new_hash).thread();
@@ -1258,7 +1259,7 @@ impl Component for ConversationsListing {
                 UIEvent::EnvelopeUpdate(ref env_hash) => {
                     let account = &context.accounts[&self.cursor_pos.0];
                     let threads = account.collection.get_threads(self.cursor_pos.1);
-                    if !account.collection.contains_key(&env_hash) {
+                    if !account.collection.contains_key(env_hash) {
                         return false;
                     }
                     let env_thread_node_hash = account.collection.get_env(*env_hash).thread();
diff --git a/src/components/mail/listing/offline.rs b/src/components/mail/listing/offline.rs
index 3aabe0ef..2c04702b 100644
--- a/src/components/mail/listing/offline.rs
+++ b/src/components/mail/listing/offline.rs
@@ -41,7 +41,7 @@ impl MailListingTrait for OfflineListing {
     }
 
     fn get_focused_items(&self, _context: &Context) -> SmallVec<[ThreadHash; 8]> {
-        return SmallVec::new();
+        SmallVec::new()
     }
 
     fn refresh_mailbox(&mut self, _context: &mut Context, _force: bool) {}
@@ -93,14 +93,14 @@ impl fmt::Display for OfflineListing {
 }
 
 impl OfflineListing {
-    pub fn new(cursor_pos: (AccountHash, MailboxHash)) -> Self {
-        OfflineListing {
+    pub fn new(cursor_pos: (AccountHash, MailboxHash)) -> Box<Self> {
+        Box::new(OfflineListing {
             cursor_pos,
             _row_updates: SmallVec::new(),
             _selection: HashMap::default(),
             dirty: true,
             id: ComponentId::new_v4(),
-        }
+        })
     }
 }
 
diff --git a/src/components/mail/listing/plain.rs b/src/components/mail/listing/plain.rs
index e8e77bcc..8b5f38a5 100644
--- a/src/components/mail/listing/plain.rs
+++ b/src/components/mail/listing/plain.rs
@@ -133,6 +133,7 @@ pub struct PlainListing {
     /// Cache current view.
     data_columns: DataColumns,
 
+    #[allow(clippy::type_complexity)]
     search_job: Option<(String, JoinHandle<Result<SmallVec<[EnvelopeHash; 512]>>>)>,
     filter_term: String,
     filtered_selection: Vec<EnvelopeHash>,
@@ -311,7 +312,7 @@ impl MailListingTrait for PlainListing {
         let roots = items
             .filter_map(|r| threads.groups[&r].root().map(|r| r.root))
             .collect::<_>();
-        let thread_nodes: &HashMap<ThreadNodeHash, ThreadNode> = &threads.thread_nodes();
+        let thread_nodes: &HashMap<ThreadNodeHash, ThreadNode> = threads.thread_nodes();
         let env_hash_iter = Box::new(
             threads
                 .threads_group_iter(roots)
@@ -685,8 +686,8 @@ impl fmt::Display for PlainListing {
 
 impl PlainListing {
     const DESCRIPTION: &'static str = "plain listing";
-    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Self {
-        PlainListing {
+    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Box<Self> {
+        Box::new(PlainListing {
             cursor_pos: (0, 1, 0),
             new_cursor_pos: (coordinates.0, coordinates.1, 0),
             length: 0,
@@ -714,7 +715,7 @@ impl PlainListing {
 
             movement: None,
             id: ComponentId::new_v4(),
-        }
+        })
     }
 
     fn make_entry_string(&self, e: EnvelopeRef, context: &Context) -> EntryStrings {
@@ -884,7 +885,7 @@ impl PlainListing {
             Box::new(self.local_collection.iter().cloned())
                 as Box<dyn Iterator<Item = EnvelopeHash>>
         } else {
-            Box::new(self.filtered_selection.iter().map(|h| *h))
+            Box::new(self.filtered_selection.iter().cloned())
                 as Box<dyn Iterator<Item = EnvelopeHash>>
         };
 
@@ -1234,7 +1235,7 @@ impl Component for PlainListing {
                             .flatten()
                             .chain(cursor_iter.into_iter().flatten())
                             .cloned();
-                        let stack: SmallVec<[_; 8]> = SmallVec::from_iter(iter.into_iter());
+                        let stack: SmallVec<[_; 8]> = SmallVec::from_iter(iter);
                         for i in stack {
                             self.perform_action(context, i, a);
                         }
diff --git a/src/components/mail/listing/thread.rs b/src/components/mail/listing/thread.rs
index 06c4e3a7..44fe2b63 100644
--- a/src/components/mail/listing/thread.rs
+++ b/src/components/mail/listing/thread.rs
@@ -241,6 +241,7 @@ impl MailListingTrait for ThreadListing {
         }
         let mut rows = Vec::with_capacity(1024);
         let mut min_width = (0, 0, 0, 0, 0);
+        #[allow(clippy::type_complexity)]
         let mut row_widths: (
             SmallVec<[u8; 1024]>,
             SmallVec<[u8; 1024]>,
@@ -260,7 +261,7 @@ impl MailListingTrait for ThreadListing {
             .filter_map(|r| threads.groups[&r].root().map(|r| r.root))
             .collect::<_>();
         let mut iter = threads.threads_group_iter(roots).peekable();
-        let thread_nodes: &HashMap<ThreadNodeHash, ThreadNode> = &threads.thread_nodes();
+        let thread_nodes: &HashMap<ThreadNodeHash, ThreadNode> = threads.thread_nodes();
         /* This is just a desugared for loop so that we can use .peek() */
         let mut idx = 0;
         let mut prev_group = ThreadHash::null();
@@ -737,8 +738,8 @@ impl fmt::Display for ThreadListing {
 }
 
 impl ThreadListing {
-    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Self {
-        ThreadListing {
+    pub fn new(coordinates: (AccountHash, MailboxHash)) -> Box<Self> {
+        Box::new(ThreadListing {
             cursor_pos: (coordinates.0, 0, 0),
             new_cursor_pos: (coordinates.0, coordinates.1, 0),
             length: 0,
@@ -757,7 +758,7 @@ impl ThreadListing {
             initialised: false,
             movement: None,
             id: ComponentId::new_v4(),
-        }
+        })
     }
 
     fn highlight_line_self(&mut self, _idx: usize, _context: &Context) {
@@ -879,7 +880,7 @@ impl ThreadListing {
         EntryStrings {
             date: DateString(ConversationsListing::format_date(context, e.date())),
             subject: SubjectString(subject),
-            flag: FlagString(format!("{}", if e.has_attachments() { "📎" } else { "" },)),
+            flag: FlagString((if e.has_attachments() { "📎" } else { "" }).to_string()),
             from: FromString(address_list!((e.from()) as comma_sep_list)),
             tags: TagString(tags, colors),
         }
@@ -1243,7 +1244,7 @@ impl Component for ThreadListing {
             }
             UIEvent::EnvelopeRename(ref old_hash, ref new_hash) => {
                 let account = &context.accounts[&self.cursor_pos.0];
-                if !account.collection.contains_key(&new_hash) {
+                if !account.collection.contains_key(new_hash) {
                     return false;
                 }
                 if let Some(row) = self.order.remove(old_hash) {
diff --git a/src/components/mail/pgp.rs b/src/components/mail/pgp.rs
index da31d671..7fce3f7f 100644
--- a/src/components/mail/pgp.rs
+++ b/src/components/mail/pgp.rs
@@ -39,7 +39,7 @@ pub async fn verify(a: Attachment) -> Result<()> {
     let (data, sig) =
         melib_pgp::verify_signature(&a).chain_err_summary(|| "Could not verify signature.")?;
     let mut ctx = Context::new()?;
-    let sig = ctx.new_data_mem(&sig.body().trim())?;
+    let sig = ctx.new_data_mem(sig.body().trim())?;
     let data = ctx.new_data_mem(&data)?;
     ctx.verify(sig, data)?.await
 }
diff --git a/src/components/mail/status.rs b/src/components/mail/status.rs
index d63e5384..5926b922 100644
--- a/src/components/mail/status.rs
+++ b/src/components/mail/status.rs
@@ -292,7 +292,7 @@ impl Component for AccountStatus {
                 None,
             );
             line += 1;
-            for (name, status) in extensions.into_iter() {
+            for (name, status) in extensions.iter() {
                 width = self.content.size().0;
                 write_string_to_grid(
                     name.trim_at_boundary(30),
@@ -418,7 +418,7 @@ impl Component for AccountStatus {
                 return true;
             }
             UIEvent::Input(ref key) if shortcut!(key == shortcuts["general"]["scroll_right"]) => {
-                self.cursor.0 = self.cursor.0 + 1;
+                self.cursor.0 += 1;
                 self.dirty = true;
                 return true;
             }
@@ -428,7 +428,7 @@ impl Component for AccountStatus {
                 return true;
             }
             UIEvent::Input(ref key) if shortcut!(key == shortcuts["general"]["scroll_down"]) => {
-                self.cursor.1 = self.cursor.1 + 1;
+                self.cursor.1 += 1;
                 self.dirty = true;
                 return true;
             }
diff --git a/src/components/mail/view.rs b/src/components/mail/view.rs
index facb81cc..47641095 100644
--- a/src/components/mail/view.rs
+++ b/src/components/mail/view.rs
@@ -58,7 +58,7 @@ enum ViewMode {
     Source(Source),
     //Ansi(RawBuffer),
     Subview,
-    ContactSelector(UIDialog<Card>),
+    ContactSelector(Box<UIDialog<Card>>),
 }
 
 impl Default for ViewMode {
@@ -76,69 +76,65 @@ impl ViewMode {
         }
     }
     */
+
     fn is_attachment(&self) -> bool {
-        match self {
-            ViewMode::Attachment(_) => true,
-            _ => false,
-        }
+        matches!(self, ViewMode::Attachment(_))
     }
+
     fn is_contact_selector(&self) -> bool {
-        match self {
-            ViewMode::ContactSelector(_) => true,
-            _ => false,
-        }
+        matches!(self, ViewMode::ContactSelector(_))
     }
 }
 
 #[derive(Debug)]
 pub enum AttachmentDisplay {
     Alternative {
-        inner: Attachment,
+        inner: Box<Attachment>,
         shown_display: usize,
         display: Vec<AttachmentDisplay>,
     },
     InlineText {
-        inner: Attachment,
+        inner: Box<Attachment>,
         comment: Option<String>,
         text: String,
     },
     InlineOther {
-        inner: Attachment,
+        inner: Box<Attachment>,
     },
     Attachment {
-        inner: Attachment,
+        inner: Box<Attachment>,
     },
     SignedPending {
-        inner: Attachment,
+        inner: Box<Attachment>,
         display: Vec<AttachmentDisplay>,
         handle: JoinHandle<Result<()>>,
         job_id: JobId,
     },
     SignedFailed {
-        inner: Attachment,
+        inner: Box<Attachment>,
         display: Vec<AttachmentDisplay>,
         error: MeliError,
     },
     SignedUnverified {
-        inner: Attachment,
+        inner: Box<Attachment>,
         display: Vec<AttachmentDisplay>,
     },
     SignedVerified {
-        inner: Attachment,
+        inner: Box<Attachment>,
         display: Vec<AttachmentDisplay>,
         description: String,
     },
     EncryptedPending {
-        inner: Attachment,
+        inner: Box<Attachment>,
         handle: JoinHandle<Result<(melib::pgp::DecryptionMetadata, Vec<u8>)>>,
     },
     EncryptedFailed {
-        inner: Attachment,
+        inner: Box<Attachment>,
         error: MeliError,
     },
     EncryptedSuccess {
-        inner: Attachment,
-        plaintext: Attachment,
+        inner: Box<Attachment>,
+        plaintext: Box<Attachment>,
         plaintext_display: Vec<AttachmentDisplay>,
         description: String,
     },
@@ -191,8 +187,8 @@ enum MailViewState {
     },
     Loaded {
         bytes: Vec<u8>,
-        env: Envelope,
-        body: Attachment,
+        env: Box<Envelope>,
+        body: Box<Attachment>,
         display: Vec<AttachmentDisplay>,
         body_text: String,
         links: Vec<Link>,
@@ -313,9 +309,10 @@ impl MailView {
                                             .get_env_mut(self.coordinates.2)
                                             .populate_headers(&bytes);
                                     }
-                                    let env =
-                                        account.collection.get_env(self.coordinates.2).clone();
-                                    let body = AttachmentBuilder::new(&bytes).build();
+                                    let env = Box::new(
+                                        account.collection.get_env(self.coordinates.2).clone(),
+                                    );
+                                    let body = Box::new(AttachmentBuilder::new(&bytes).build());
                                     let display = Self::attachment_to(
                                         &body,
                                         context,
@@ -415,7 +412,7 @@ impl MailView {
                 ..
             } => (
                 bytes,
-                self.attachment_displays_to_text(&display, context, false),
+                self.attachment_displays_to_text(display, context, false),
                 env,
             ),
             MailViewState::Error { .. } => {
@@ -489,13 +486,13 @@ impl MailView {
                     if !acc.ends_with("\n\n") {
                         acc.push_str("\n\n");
                     }
-                    acc.push_str(&text);
+                    acc.push_str(text);
                 }
                 InlineText {
                     inner: _,
                     text,
                     comment: _,
-                } => acc.push_str(&text),
+                } => acc.push_str(text),
                 InlineOther { inner } => {
                     if !acc.ends_with("\n\n") {
                         acc.push_str("\n\n");
@@ -550,7 +547,7 @@ impl MailView {
                         if description.is_empty() {
                             acc.push_str("Verified signature.\n\n");
                         } else {
-                            acc.push_str(&description);
+                            acc.push_str(description);
                             acc.push_str("\n\n");
                         }
                     }
@@ -574,7 +571,7 @@ impl MailView {
                         if description.is_empty() {
                             acc.push_str("Succesfully decrypted.\n\n");
                         } else {
-                            acc.push_str(&description);
+                            acc.push_str(description);
                             acc.push_str("\n\n");
                         }
                     }
@@ -672,35 +669,32 @@ impl MailView {
                 s.push(' ');
             }
 
-            s.extend(att.to_string().chars());
+            s.push_str(&att.to_string());
             paths.push(cur_path.clone());
-            match att.content_type {
-                ContentType::Multipart { .. } => {
-                    let mut iter = (0..sub_att_display_vec.len()).peekable();
-                    if has_sibling {
-                        branches.push(true);
-                    } else {
-                        branches.push(false);
-                    }
-                    while let Some(i) = iter.next() {
-                        *idx += 1;
-                        cur_path.push(i);
-                        append_entry(
-                            (idx, (depth + 1, &sub_att_display_vec[i])),
-                            branches,
-                            paths,
-                            cur_path,
-                            iter.peek() != None,
-                            s,
-                        );
-                        if Some(i) == default_alternative {
-                            s.push_str(" (displayed by default)");
-                        }
-                        cur_path.pop();
-                    }
-                    branches.pop();
+            if matches!(att.content_type, ContentType::Multipart { .. }) {
+                let mut iter = (0..sub_att_display_vec.len()).peekable();
+                if has_sibling {
+                    branches.push(true);
+                } else {
+                    branches.push(false);
                 }
-                _ => {}
+                while let Some(i) = iter.next() {
+                    *idx += 1;
+                    cur_path.push(i);
+                    append_entry(
+                        (idx, (depth + 1, &sub_att_display_vec[i])),
+                        branches,
+                        paths,
+                        cur_path,
+                        iter.peek() != None,
+                        s,
+                    );
+                    if Some(i) == default_alternative {
+                        s.push_str(" (displayed by default)");
+                    }
+                    cur_path.pop();
+                }
+                branches.pop();
             }
         }
 
@@ -735,7 +729,9 @@ impl MailView {
             active_jobs: &mut HashSet<JobId>,
         ) {
             if a.content_disposition.kind.is_attachment() || a.content_type == "message/rfc822" {
-                acc.push(AttachmentDisplay::Attachment { inner: a.clone() });
+                acc.push(AttachmentDisplay::Attachment {
+                    inner: Box::new(a.clone()),
+                });
             } else if a.content_type().is_text_html() {
                 let bytes = decode(a, None);
                 let filter_invocation =
@@ -764,7 +760,7 @@ impl MailView {
                             ));
                         let text = String::from_utf8_lossy(&bytes).to_string();
                         acc.push(AttachmentDisplay::InlineText {
-                            inner: a.clone(),
+                            inner: Box::new(a.clone()),
                             comment,
                             text,
                         });
@@ -785,7 +781,7 @@ impl MailView {
                         )
                         .to_string();
                         acc.push(AttachmentDisplay::InlineText {
-                            inner: a.clone(),
+                            inner: Box::new(a.clone()),
                             comment,
                             text,
                         });
@@ -794,7 +790,7 @@ impl MailView {
             } else if a.is_text() {
                 let bytes = decode(a, None);
                 acc.push(AttachmentDisplay::InlineText {
-                    inner: a.clone(),
+                    inner: Box::new(a.clone()),
                     comment: None,
                     text: String::from_utf8_lossy(&bytes).to_string(),
                 });
@@ -838,7 +834,7 @@ impl MailView {
                             rec(a, context, coordinates, &mut display, active_jobs);
                         }
                         acc.push(AttachmentDisplay::Alternative {
-                            inner: a.clone(),
+                            inner: Box::new(a.clone()),
                             shown_display: chosen_attachment_idx,
                             display,
                         });
@@ -847,7 +843,7 @@ impl MailView {
                         #[cfg(not(feature = "gpgme"))]
                         {
                             acc.push(AttachmentDisplay::SignedUnverified {
-                                inner: a.clone(),
+                                inner: Box::new(a.clone()),
                                 display: {
                                     let mut v = vec![];
                                     rec(&parts[0], context, coordinates, &mut v, active_jobs);
@@ -869,7 +865,7 @@ impl MailView {
                                     StatusEvent::NewJob(handle.job_id),
                                 ));
                                 acc.push(AttachmentDisplay::SignedPending {
-                                    inner: a.clone(),
+                                    inner: Box::new(a.clone()),
                                     job_id: handle.job_id,
                                     display: {
                                         let mut v = vec![];
@@ -880,7 +876,7 @@ impl MailView {
                                 });
                             } else {
                                 acc.push(AttachmentDisplay::SignedUnverified {
-                                    inner: a.clone(),
+                                    inner: Box::new(a.clone()),
                                     display: {
                                         let mut v = vec![];
                                         rec(&parts[0], context, coordinates, &mut v, active_jobs);
@@ -896,7 +892,7 @@ impl MailView {
                                 #[cfg(not(feature = "gpgme"))]
                                 {
                                     acc.push(AttachmentDisplay::EncryptedFailed {
-                                                inner: a.clone(),
+                                    inner: Box::new(a.clone()),
                                                 error: MeliError::new("Cannot decrypt: meli must be compiled with libgpgme support."),
                                             });
                                 }
@@ -914,12 +910,12 @@ impl MailView {
                                             StatusEvent::NewJob(handle.job_id),
                                         ));
                                         acc.push(AttachmentDisplay::EncryptedPending {
-                                            inner: a.clone(),
+                                            inner: Box::new(a.clone()),
                                             handle,
                                         });
                                     } else {
                                         acc.push(AttachmentDisplay::EncryptedFailed {
-                                            inner: a.clone(),
+                                            inner: Box::new(a.clone()),
                                             error: MeliError::new("Undecrypted."),
                                         });
                                     }
@@ -963,17 +959,13 @@ impl MailView {
         } else {
             return None;
         };
-        if let Some(path) =
-            self.attachment_paths.get(lidx).and_then(
-                |path| {
-                    if path.len() > 0 {
-                        Some(path)
-                    } else {
-                        None
-                    }
-                },
-            )
-        {
+        if let Some(path) = self.attachment_paths.get(lidx).and_then(|path| {
+            if !path.is_empty() {
+                Some(path)
+            } else {
+                None
+            }
+        }) {
             let first = path[0];
             use AttachmentDisplay::*;
             let root_attachment = match &display[first] {
@@ -1022,14 +1014,11 @@ impl MailView {
                 if path.is_empty() {
                     return Some(a);
                 }
-                match a.content_type {
-                    ContentType::Multipart { ref parts, .. } => {
-                        let first = path[0];
-                        if first < parts.len() {
-                            return find_attachment(&parts[first], &path[1..]);
-                        }
+                if let ContentType::Multipart { ref parts, .. } = a.content_type {
+                    let first = path[0];
+                    if first < parts.len() {
+                        return find_attachment(&parts[first], &path[1..]);
                     }
-                    _ => {}
                 }
                 None
             }
@@ -1080,7 +1069,7 @@ impl MailView {
             entries.push((new_card, format!("{}", addr)));
         }
         drop(envelope);
-        self.mode = ViewMode::ContactSelector(Selector::new(
+        self.mode = ViewMode::ContactSelector(Box::new(Selector::new(
             "select contacts to add",
             entries,
             false,
@@ -1088,7 +1077,7 @@ impl MailView {
                 Some(UIEvent::FinishedUIDialog(id, Box::new(results.to_vec())))
             })),
             context,
-        ));
+        )));
         self.dirty = true;
         self.initialised = false;
     }
@@ -1420,10 +1409,7 @@ impl Component for MailView {
                     err.to_string(),
                     Some(NotificationType::Error(err.kind)),
                 ));
-                log(
-                    format!("Failed to open envelope: {}", err.to_string()),
-                    ERROR,
-                );
+                log(format!("Failed to open envelope: {}", err), ERROR);
                 self.init_futures(context);
                 return;
             } else {
@@ -1444,7 +1430,7 @@ impl Component for MailView {
                     let mut text = "Viewing attachment. Press `r` to return \n".to_string();
                     if let Some(attachment) = self.open_attachment(aidx, context) {
                         if attachment.is_html() {
-                            self.subview = Some(Box::new(HtmlView::new(&attachment, context)));
+                            self.subview = Some(Box::new(HtmlView::new(attachment, context)));
                             self.mode = ViewMode::Subview;
                         } else {
                             text.push_str(&attachment.text());
@@ -1475,7 +1461,7 @@ impl Component for MailView {
                     }
                 }
                 ViewMode::Normal if body.is_html() => {
-                    self.subview = Some(Box::new(HtmlView::new(&body, context)));
+                    self.subview = Some(Box::new(HtmlView::new(body, context)));
                     self.mode = ViewMode::Subview;
                 }
                 ViewMode::Normal
@@ -1497,13 +1483,12 @@ impl Component for MailView {
                         } =>
                 {
                     self.subview = Some(Box::new(HtmlView::new(
-                        &body
-                            .content_type
+                        body.content_type
                             .parts()
                             .unwrap()
-                            .into_iter()
+                            .iter()
                             .find(|a| a.is_html())
-                            .unwrap_or(&body),
+                            .unwrap_or(body),
                         context,
                     )));
                     self.mode = ViewMode::Subview;
@@ -1541,7 +1526,7 @@ impl Component for MailView {
                             if !ret.ends_with("\n\n") {
                                 ret.push_str("\n\n");
                             }
-                            ret.extend(body_text.chars());
+                            ret.push_str(body_text);
                             if !ret.ends_with("\n\n") {
                                 ret.push_str("\n\n");
                             }
@@ -1721,10 +1706,8 @@ impl Component for MailView {
                     self.force_draw_headers = true;
                     if self.pager.cursor_pos() == 0 {
                         self.headers_cursor = self.headers_cursor.saturating_sub(1);
-                    } else {
-                        if self.pager.process_event(event, context) {
-                            return true;
-                        }
+                    } else if self.pager.process_event(event, context) {
+                        return true;
                     }
                     self.pager.set_dirty(true);
                     return true;
@@ -1767,11 +1750,13 @@ impl Component for MailView {
                                             .get_env_mut(self.coordinates.2)
                                             .populate_headers(&bytes);
                                     }
-                                    let env = context.accounts[&self.coordinates.0]
-                                        .collection
-                                        .get_env(self.coordinates.2)
-                                        .clone();
-                                    let body = AttachmentBuilder::new(&bytes).build();
+                                    let env = Box::new(
+                                        context.accounts[&self.coordinates.0]
+                                            .collection
+                                            .get_env(self.coordinates.2)
+                                            .clone(),
+                                    );
+                                    let body = Box::new(AttachmentBuilder::new(&bytes).build());
                                     let display = Self::attachment_to(
                                         &body,
                                         context,
@@ -1823,9 +1808,11 @@ impl Component for MailView {
                                                 *d = AttachmentDisplay::SignedVerified {
                                                     inner: std::mem::replace(
                                                         inner,
-                                                        AttachmentBuilder::new(&[]).build(),
+                                                        Box::new(
+                                                            AttachmentBuilder::new(&[]).build(),
+                                                        ),
                                                     ),
-                                                    display: std::mem::replace(display, vec![]),
+                                                    display: std::mem::take(display),
                                                     description: String::new(),
                                                 };
                                             }
@@ -1833,9 +1820,11 @@ impl Component for MailView {
                                                 *d = AttachmentDisplay::SignedFailed {
                                                     inner: std::mem::replace(
                                                         inner,
-                                                        AttachmentBuilder::new(&[]).build(),
+                                                        Box::new(
+                                                            AttachmentBuilder::new(&[]).build(),
+                                                        ),
                                                     ),
-                                                    display: std::mem::replace(display, vec![]),
+                                                    display: std::mem::take(display),
                                                     error,
                                                 };
                                             }
@@ -1851,9 +1840,10 @@ impl Component for MailView {
                                             Ok(None) => { /* something happened, perhaps a worker thread panicked */
                                             }
                                             Ok(Some(Ok((metadata, decrypted_bytes)))) => {
-                                                let plaintext =
+                                                let plaintext = Box::new(
                                                     AttachmentBuilder::new(&decrypted_bytes)
-                                                        .build();
+                                                        .build(),
+                                                );
                                                 let plaintext_display = Self::attachment_to(
                                                     &plaintext,
                                                     context,
@@ -1863,7 +1853,9 @@ impl Component for MailView {
                                                 *d = AttachmentDisplay::EncryptedSuccess {
                                                     inner: std::mem::replace(
                                                         inner,
-                                                        AttachmentBuilder::new(&[]).build(),
+                                                        Box::new(
+                                                            AttachmentBuilder::new(&[]).build(),
+                                                        ),
                                                     ),
                                                     plaintext,
                                                     plaintext_display,
@@ -1874,7 +1866,9 @@ impl Component for MailView {
                                                 *d = AttachmentDisplay::EncryptedFailed {
                                                     inner: std::mem::replace(
                                                         inner,
-                                                        AttachmentBuilder::new(&[]).build(),
+                                                        Box::new(
+                                                            AttachmentBuilder::new(&[]).build(),
+                                                        ),
                                                     ),
                                                     error,
                                                 };
@@ -1888,9 +1882,9 @@ impl Component for MailView {
                                 let mut new_body_text = String::new();
                                 if let MailViewState::Loaded { ref display, .. } = self.state {
                                     new_body_text =
-                                        self.attachment_displays_to_text(&display, context, true);
+                                        self.attachment_displays_to_text(display, context, true);
                                     let (paths, attachment_tree_s) =
-                                        self.attachment_displays_to_tree(&display);
+                                        self.attachment_displays_to_tree(display);
                                     self.attachment_tree = attachment_tree_s;
                                     self.attachment_paths = paths;
                                 }
@@ -2042,7 +2036,7 @@ impl Component for MailView {
                                                 .get(&env_hash)
                                                 .map(|env| env.message_id_display())
                                                 .unwrap_or_else(|| "Not found".into()),
-                                                err.to_string()
+                                                err
                                             );
                                             log(&err_string, ERROR);
                                             context.replies.push_back(UIEvent::Notification(
@@ -2088,7 +2082,7 @@ impl Component for MailView {
                     .push_back(UIEvent::StatusEvent(StatusEvent::BufClear));
                 return true;
             }
-            UIEvent::Input(Key::Char(c)) if c >= '0' && c <= '9' => {
+            UIEvent::Input(Key::Char(c)) if ('0'..='9').contains(&c) => {
                 self.cmd_buf.push(c);
                 context
                     .replies
@@ -2218,7 +2212,7 @@ impl Component for MailView {
                                     if let Ok(command) = query_default_app(&attachment_type) {
                                         let p = create_temp_file(
                                             &decode(attachment, None),
-                                            filename.as_ref().map(|s| s.as_str()),
+                                            filename.as_deref(),
                                             None,
                                             true,
                                         );
@@ -2400,10 +2394,7 @@ impl Component for MailView {
                         err.to_string(),
                         Some(NotificationType::Error(err.kind)),
                     ));
-                    log(
-                        format!("Failed to open envelope: {}", err.to_string()),
-                        ERROR,
-                    );
+                    log(format!("Failed to open envelope: {}", err), ERROR);
                     self.init_futures(context);
                     return true;
                 } else {
@@ -2424,11 +2415,7 @@ impl Component for MailView {
                             Some(NotificationType::Error(melib::ErrorKind::External)),
                         ));
                         log(
-                            format!(
-                                "Failed to create file at {}: {}",
-                                path.display(),
-                                err.to_string()
-                            ),
+                            format!("Failed to create file at {}: {}", path.display(), err),
                             ERROR,
                         );
                         return true;
@@ -2461,10 +2448,7 @@ impl Component for MailView {
                         err.to_string(),
                         Some(NotificationType::Error(err.kind)),
                     ));
-                    log(
-                        format!("Failed to open envelope: {}", err.to_string()),
-                        ERROR,
-                    );
+                    log(format!("Failed to open envelope: {}", err), ERROR);
                     self.init_futures(context);
                     return true;
                 } else {
@@ -2490,11 +2474,7 @@ impl Component for MailView {
                                 Some(NotificationType::Error(melib::ErrorKind::External)),
                             ));
                             log(
-                                format!(
-                                    "Failed to create file at {}: {}",
-                                    path.display(),
-                                    err.to_string()
-                                ),
+                                format!("Failed to create file at {}: {}", path.display(), err),
                                 ERROR,
                             );
                         }
@@ -2521,11 +2501,7 @@ impl Component for MailView {
                                 Some(NotificationType::Error(melib::ErrorKind::External)),
                             ));
                             log(
-                                format!(
-                                    "Failed to create file at {}: {}",
-                                    path.display(),
-                                    err.to_string()
-                                ),
+                                format!("Failed to create file at {}: {}", path.display(), err),
                                 ERROR,
                             );
                             return true;
diff --git a/src/components/mail/view/envelope.rs b/src/components/mail/view/envelope.rs
index 9e1ccda8..2861c337 100644
--- a/src/components/mail/view/envelope.rs
+++ b/src/components/mail/view/envelope.rs
@@ -36,10 +36,7 @@ enum ViewMode {
 
 impl ViewMode {
     fn is_attachment(&self) -> bool {
-        match self {
-            ViewMode::Attachment(_) => true,
-            _ => false,
-        }
+        matches!(self, ViewMode::Attachment(_))
     }
 }
 
@@ -53,7 +50,7 @@ pub struct EnvelopeView {
     mode: ViewMode,
     mail: Mail,
 
-    account_hash: AccountHash,
+    _account_hash: AccountHash,
     cmd_buf: String,
     id: ComponentId,
 }
@@ -69,7 +66,7 @@ impl EnvelopeView {
         mail: Mail,
         pager: Option<Pager>,
         subview: Option<Box<dyn Component>>,
-        account_hash: AccountHash,
+        _account_hash: AccountHash,
     ) -> Self {
         EnvelopeView {
             pager,
@@ -77,7 +74,7 @@ impl EnvelopeView {
             dirty: true,
             mode: ViewMode::Normal,
             mail,
-            account_hash,
+            _account_hash,
             cmd_buf: String::with_capacity(4),
             id: ComponentId::new_v4(),
         }
@@ -87,7 +84,7 @@ impl EnvelopeView {
     fn attachment_to_text(&self, body: &Attachment, context: &mut Context) -> String {
         let finder = LinkFinder::new();
         let body_text = String::from_utf8_lossy(&decode_rec(
-            &body,
+            body,
             Some(Box::new(|a: &Attachment, v: &mut Vec<u8>| {
                 if a.content_type().is_text_html() {
                     let settings = &context.settings;
@@ -107,14 +104,13 @@ impl EnvelopeView {
                                     err.to_string(),
                                     Some(NotificationType::Error(melib::ErrorKind::External)),
                                 ));
-                                return;
                             }
                             Ok(mut html_filter) => {
                                 html_filter
                                     .stdin
                                     .as_mut()
                                     .unwrap()
-                                    .write_all(&v)
+                                    .write_all(v)
                                     .expect("Failed to write to stdin");
                                 *v = format!(
                             "Text piped through `{}`. Press `v` to open in web browser. \n\n",
@@ -286,7 +282,7 @@ impl Component for EnvelopeView {
             match self.mode {
                 ViewMode::Attachment(aidx) if body.attachments()[aidx].is_html() => {
                     let attachment = &body.attachments()[aidx];
-                    self.subview = Some(Box::new(HtmlView::new(&attachment, context)));
+                    self.subview = Some(Box::new(HtmlView::new(attachment, context)));
                 }
                 ViewMode::Normal if body.is_html() => {
                     self.subview = Some(Box::new(HtmlView::new(&body, context)));
@@ -336,7 +332,7 @@ impl Component for EnvelopeView {
                     .push_back(UIEvent::StatusEvent(StatusEvent::BufClear));
                 return true;
             }
-            UIEvent::Input(Key::Char(c)) if c >= '0' && c <= '9' => {
+            UIEvent::Input(Key::Char(c)) if ('0'..='9').contains(&c) => {
                 self.cmd_buf.push(c);
                 return true;
             }
@@ -368,71 +364,70 @@ impl Component for EnvelopeView {
                     .replies
                     .push_back(UIEvent::StatusEvent(StatusEvent::BufClear));
 
-                {
-                    if let Some(u) = self.mail.body().attachments().get(lidx) {
-                        match u.content_type() {
-                            ContentType::MessageRfc822 => {
-                                self.mode = ViewMode::Subview;
-                                let colors = crate::conf::value(context, "mail.view.body");
-                                self.subview = Some(Box::new(Pager::from_string(
-                                    String::from_utf8_lossy(&decode_rec(u, None)).to_string(),
-                                    Some(context),
-                                    None,
-                                    None,
-                                    colors,
-                                )));
-                            }
+                if let Some(u) = self.mail.body().attachments().get(lidx) {
+                    match u.content_type() {
+                        ContentType::MessageRfc822 => {
+                            self.mode = ViewMode::Subview;
+                            let colors = crate::conf::value(context, "mail.view.body");
+                            self.subview = Some(Box::new(Pager::from_string(
+                                String::from_utf8_lossy(&decode_rec(u, None)).to_string(),
+                                Some(context),
+                                None,
+                                None,
+                                colors,
+                            )));
+                        }
 
-                            ContentType::Text { .. }
-                            | ContentType::PGPSignature
-                            | ContentType::CMSSignature => {
-                                self.mode = ViewMode::Attachment(lidx);
-                                self.dirty = true;
-                            }
-                            ContentType::Multipart { .. } => {
-                                context.replies.push_back(UIEvent::StatusEvent(
-                                    StatusEvent::DisplayMessage(
-                                        "Multipart attachments are not supported yet.".to_string(),
-                                    ),
-                                ));
-                                return true;
-                            }
-                            ContentType::Other { .. } => {
-                                let attachment_type = u.mime_type();
-                                let filename = u.filename();
-                                if let Ok(command) = query_default_app(&attachment_type) {
-                                    let p = create_temp_file(
-                                        &decode(u, None),
-                                        filename.as_ref().map(|s| s.as_str()),
-                                        None,
-                                        true,
-                                    );
-                                    let (exec_cmd, argument) = super::desktop_exec_to_command(
-                                        &command,
-                                        p.path.display().to_string(),
-                                        false,
-                                    );
-                                    match Command::new(&exec_cmd)
-                                        .arg(&argument)
-                                        .stdin(Stdio::piped())
-                                        .stdout(Stdio::piped())
-                                        .spawn()
-                                    {
-                                        Ok(child) => {
-                                            context.temp_files.push(p);
-                                            context.children.push(child);
-                                        }
-                                        Err(err) => {
-                                            context.replies.push_back(UIEvent::StatusEvent(
-                                                StatusEvent::DisplayMessage(format!(
-                                                    "Failed to start `{} {}`: {}",
-                                                    &exec_cmd, &argument, err
-                                                )),
-                                            ));
-                                        }
+                        ContentType::Text { .. }
+                        | ContentType::PGPSignature
+                        | ContentType::CMSSignature => {
+                            self.mode = ViewMode::Attachment(lidx);
+                            self.dirty = true;
+                        }
+                        ContentType::Multipart { .. } => {
+                            context.replies.push_back(UIEvent::StatusEvent(
+                                StatusEvent::DisplayMessage(
+                                    "Multipart attachments are not supported yet.".to_string(),
+                                ),
+                            ));
+                            return true;
+                        }
+                        ContentType::Other { .. } => {
+                            let attachment_type = u.mime_type();
+                            let filename = u.filename();
+                            if let Ok(command) = query_default_app(&attachment_type) {
+                                let p = create_temp_file(
+                                    &decode(u, None),
+                                    filename.as_deref(),
+                                    None,
+                                    true,
+                                );
+                                let (exec_cmd, argument) = super::desktop_exec_to_command(
+                                    &command,
+                                    p.path.display().to_string(),
+                                    false,
+                                );
+                                match Command::new(&exec_cmd)
+                                    .arg(&argument)
+                                    .stdin(Stdio::piped())
+                                    .stdout(Stdio::piped())
+                                    .spawn()
+                                {
+                                    Ok(child) => {
+                                        context.temp_files.push(p);
+                                        context.children.push(child);
                                     }
-                                } else {
-                                    context.replies.push_back(UIEvent::StatusEvent(
+                                    Err(err) => {
+                                        context.replies.push_back(UIEvent::StatusEvent(
+                                            StatusEvent::DisplayMessage(format!(
+                                                "Failed to start `{} {}`: {}",
+                                                &exec_cmd, &argument, err
+                                            )),
+                                        ));
+                                    }
+                                }
+                            } else {
+                                context.replies.push_back(UIEvent::StatusEvent(
                                         StatusEvent::DisplayMessage(if let Some(filename) = filename.as_ref() {
                                             format!(
                                                 "Couldn't find a default application for file {} (type {})",
@@ -445,29 +440,28 @@ impl Component for EnvelopeView {
                                                 attachment_type
                                             )
                                         }),
-                                ));
-                                    return true;
-                                }
-                            }
-                            ContentType::OctetStream { .. } => {
-                                context.replies.push_back(UIEvent::StatusEvent(
-                                    StatusEvent::DisplayMessage(
-                                        "application/octet-stream isn't supported yet".to_string(),
-                                    ),
                                 ));
                                 return true;
                             }
                         }
-                    } else {
-                        context.replies.push_back(UIEvent::StatusEvent(
-                            StatusEvent::DisplayMessage(format!(
-                                "Attachment `{}` not found.",
-                                lidx
-                            )),
-                        ));
-                        return true;
+                        ContentType::OctetStream { .. } => {
+                            context.replies.push_back(UIEvent::StatusEvent(
+                                StatusEvent::DisplayMessage(
+                                    "application/octet-stream isn't supported yet".to_string(),
+                                ),
+                            ));
+                            return true;
+                        }
                     }
-                };
+                } else {
+                    context
+                        .replies
+                        .push_back(UIEvent::StatusEvent(StatusEvent::DisplayMessage(format!(
+                            "Attachment `{}` not found.",
+                            lidx
+                        ))));
+                    return true;
+                }
                 return true;
             }
             UIEvent::Input(Key::Char('g'))
@@ -492,22 +486,16 @@ impl Component for EnvelopeView {
                     }
                 };
 
-                let url_launcher = context
-                    .settings
-                    .pager
-                    .url_launcher
-                    .as_ref()
-                    .map(|s| s.as_str())
-                    .unwrap_or(
-                        #[cfg(target_os = "macos")]
-                        {
-                            "open"
-                        },
-                        #[cfg(not(target_os = "macos"))]
-                        {
-                            "xdg-open"
-                        },
-                    );
+                let url_launcher = context.settings.pager.url_launcher.as_deref().unwrap_or(
+                    #[cfg(target_os = "macos")]
+                    {
+                        "open"
+                    },
+                    #[cfg(not(target_os = "macos"))]
+                    {
+                        "xdg-open"
+                    },
+                );
                 match Command::new(url_launcher)
                     .arg(url)
                     .stdin(Stdio::piped())
diff --git a/src/components/mail/view/thread.rs b/src/components/mail/view/thread.rs
index 3601bdbc..34001386 100644
--- a/src/components/mail/view/thread.rs
+++ b/src/components/mail/view/thread.rs
@@ -415,11 +415,7 @@ impl ThreadView {
         idx: usize,
         context: &Context,
     ) {
-        let visibles: Vec<&usize> = self
-            .visible_entries
-            .iter()
-            .flat_map(|ref v| v.iter())
-            .collect();
+        let visibles: Vec<&usize> = self.visible_entries.iter().flat_map(|v| v.iter()).collect();
         if idx == *visibles[self.cursor_pos] {
             let theme_default = crate::conf::value(context, "theme_default");
             let bg_color = crate::conf::value(context, "highlight").bg;
@@ -514,11 +510,8 @@ impl ThreadView {
             if page_no != prev_page_no {
                 clear_area(grid, area, crate::conf::value(context, "theme_default"));
             }
-            let visibles: Vec<&usize> = self
-                .visible_entries
-                .iter()
-                .flat_map(|ref v| v.iter())
-                .collect();
+            let visibles: Vec<&usize> =
+                self.visible_entries.iter().flat_map(|v| v.iter()).collect();
 
             for (visible_entry_counter, v) in visibles.iter().skip(top_idx).take(rows).enumerate() {
                 if visible_entry_counter >= rows {
@@ -595,11 +588,8 @@ impl ThreadView {
             self.cursor_pos = self.new_cursor_pos;
             /* If cursor position has changed, remove the highlight from the previous position and
              * apply it in the new one. */
-            let visibles: Vec<&usize> = self
-                .visible_entries
-                .iter()
-                .flat_map(|ref v| v.iter())
-                .collect();
+            let visibles: Vec<&usize> =
+                self.visible_entries.iter().flat_map(|v| v.iter()).collect();
             for &idx in &[old_cursor_pos, self.cursor_pos] {
                 let entry_idx = *visibles[idx];
                 let src_area = { get_entry_area(entry_idx, &self.entries) };
@@ -948,11 +938,7 @@ impl ThreadView {
 
     /// Current position in self.entries (not in drawn entries which might exclude nonvisible ones)
     fn current_pos(&self) -> usize {
-        let visibles: Vec<&usize> = self
-            .visible_entries
-            .iter()
-            .flat_map(|ref v| v.iter())
-            .collect();
+        let visibles: Vec<&usize> = self.visible_entries.iter().flat_map(|v| v.iter()).collect();
         *visibles[self.new_cursor_pos]
     }
 }
@@ -999,15 +985,12 @@ impl Component for ThreadView {
         self.dirty = false;
     }
     fn process_event(&mut self, event: &mut UIEvent, context: &mut Context) -> bool {
-        match event {
-            UIEvent::Action(Listing(OpenInNewTab)) => {
-                /* Handle this before self.mailview does */
-                context
-                    .replies
-                    .push_back(UIEvent::Action(Tab(New(Some(Box::new(self.clone()))))));
-                return true;
-            }
-            _ => {}
+        if let UIEvent::Action(Listing(OpenInNewTab)) = event {
+            /* Handle this before self.mailview does */
+            context
+                .replies
+                .push_back(UIEvent::Action(Tab(New(Some(Box::new(self.clone()))))));
+            return true;
         }
 
         if self.show_mailview && self.mailview.process_event(event, context) {
diff --git a/src/components/notifications.rs b/src/components/notifications.rs
index 1d676e66..caf85f94 100644
--- a/src/components/notifications.rs
+++ b/src/components/notifications.rs
@@ -169,7 +169,7 @@ mod dbus {
 }
 
 /// Passes notifications to a user defined shell command
-#[derive(Debug)]
+#[derive(Default, Debug)]
 pub struct NotificationCommand {}
 
 impl NotificationCommand {
@@ -204,7 +204,7 @@ impl Component for NotificationCommand {
                         }
                         Err(err) => {
                             log(
-                                format!("Could not run notification script: {}.", err.to_string()),
+                                format!("Could not run notification script: {}.", err),
                                 ERROR,
                             );
                             debug!("Could not run notification script: {:?}", err);
@@ -226,10 +226,7 @@ impl Component for NotificationCommand {
                             }
                             Err(err) => {
                                 log(
-                                    format!(
-                                        "Could not run notification script: {}.",
-                                        err.to_string()
-                                    ),
+                                    format!("Could not run notification script: {}.", err),
                                     ERROR,
                                 );
                                 debug!("Could not run notification script: {:?}", err);
diff --git a/src/components/utilities.rs b/src/components/utilities.rs
index 4feadbef..b8a98880 100644
--- a/src/components/utilities.rs
+++ b/src/components/utilities.rs
@@ -67,7 +67,7 @@ pub struct StatusBar {
     done_jobs: HashSet<JobId>,
     scroll_contexts: IndexMap<ComponentId, ScrollContext>,
 
-    auto_complete: AutoComplete,
+    auto_complete: Box<AutoComplete>,
     cmd_history: Vec<String>,
 }
 
@@ -136,7 +136,7 @@ impl StatusBar {
                 .set_bg(attribute.bg)
                 .set_attrs(attribute.attrs);
         }
-        let offset = self.status.find('|').unwrap_or_else(|| self.status.len());
+        let offset = self.status.find('|').unwrap_or(self.status.len());
         if y < get_y(bottom_right!(area)) + 1 {
             for x in get_x(upper_left!(area))
                 ..std::cmp::min(
@@ -209,8 +209,7 @@ impl StatusBar {
                     .settings
                     .terminal
                     .mouse_flag
-                    .as_ref()
-                    .map(|s| s.as_str())
+                    .as_deref()
                     .unwrap_or("🖱️ ")
             } else {
                 ""
@@ -362,7 +361,7 @@ impl Component for StatusBar {
                 }
 
                 suggestions.sort_by(|a, b| a.entry.cmp(&b.entry));
-                suggestions.dedup_by(|a, b| &a.entry == &b.entry);
+                suggestions.dedup_by(|a, b| a.entry == b.entry);
                 if self.auto_complete.set_suggestions(suggestions) {
                     let len = self.auto_complete.suggestions().len() - 1;
                     self.auto_complete.set_cursor(len);
@@ -529,7 +528,7 @@ impl Component for StatusBar {
                 self.container.set_dirty(true);
             }
             UIEvent::ChangeMode(m) => {
-                let offset = self.status.find('|').unwrap_or_else(|| self.status.len());
+                let offset = self.status.find('|').unwrap_or(self.status.len());
                 self.status.replace_range(
                     ..offset,
                     &format!(
@@ -540,8 +539,7 @@ impl Component for StatusBar {
                                 .settings
                                 .terminal
                                 .mouse_flag
-                                .as_ref()
-                                .map(|s| s.as_str())
+                                .as_deref()
                                 .unwrap_or("🖱️ ")
                         } else {
                             ""
@@ -559,7 +557,7 @@ impl Component for StatusBar {
                                 .replies
                                 .push_back(UIEvent::Command(self.ex_buffer.as_str().to_string()));
                         }
-                        if parse_command(&self.ex_buffer.as_str().as_bytes()).is_ok()
+                        if parse_command(self.ex_buffer.as_str().as_bytes()).is_ok()
                             && self.cmd_history.last().map(String::as_str)
                                 != Some(self.ex_buffer.as_str())
                         {
@@ -1138,7 +1136,7 @@ impl Component for Tabbed {
                         None,
                     );
                     write_string_to_grid(
-                        &k,
+                        k,
                         &mut self.help_content,
                         self.theme_default.fg,
                         self.theme_default.bg,
@@ -1485,13 +1483,13 @@ impl Component for Tabbed {
                         self.help_screen_cursor.1 = self.help_screen_cursor.1.saturating_sub(1);
                     }
                     _ if shortcut!(key == shortcuts["general"]["scroll_down"]) => {
-                        self.help_screen_cursor.1 = self.help_screen_cursor.1 + 1;
+                        self.help_screen_cursor.1 += 1;
                     }
                     _ if shortcut!(key == shortcuts["general"]["scroll_left"]) => {
                         self.help_screen_cursor.0 = self.help_screen_cursor.0.saturating_sub(1);
                     }
                     _ if shortcut!(key == shortcuts["general"]["scroll_right"]) => {
-                        self.help_screen_cursor.0 = self.help_screen_cursor.0 + 1;
+                        self.help_screen_cursor.0 += 1;
                     }
                     _ => {
                         /* ignore, don't pass to components below the shortcut panel */
@@ -1600,7 +1598,7 @@ impl Component for RawBuffer {
                 true
             }
             UIEvent::Input(Key::Right) => {
-                self.cursor.0 = self.cursor.0 + 1;
+                self.cursor.0 += 1;
                 self.dirty = true;
                 true
             }
@@ -1610,7 +1608,7 @@ impl Component for RawBuffer {
                 true
             }
             UIEvent::Input(Key::Down) => {
-                self.cursor.1 = self.cursor.1 + 1;
+                self.cursor.1 += 1;
                 self.dirty = true;
                 true
             }
@@ -1641,9 +1639,6 @@ impl RawBuffer {
         }
     }
     pub fn title(&self) -> &str {
-        self.title
-            .as_ref()
-            .map(String::as_str)
-            .unwrap_or("untitled")
+        self.title.as_deref().unwrap_or("untitled")
     }
 }
diff --git a/src/components/utilities/dialogs.rs b/src/components/utilities/dialogs.rs
index 747cb3ce..1cdac8c1 100644
--- a/src/components/utilities/dialogs.rs
+++ b/src/components/utilities/dialogs.rs
@@ -760,7 +760,7 @@ impl<T: PartialEq + Debug + Clone + Sync + Send, F: 'static + Sync + Send> Selec
     ) -> Selector<T, F> {
         let entry_titles = entries
             .iter_mut()
-            .map(|(_id, ref mut title)| std::mem::replace(title, String::new()))
+            .map(|(_id, ref mut title)| std::mem::take(title))
             .collect::<Vec<String>>();
         let mut identifiers: Vec<(T, bool)> =
             entries.into_iter().map(|(id, _)| (id, false)).collect();
@@ -812,7 +812,7 @@ impl<T: PartialEq + Debug + Clone + Sync + Send, F: 'static + Sync + Send> Selec
         if self.single_only {
             for (i, e) in self.entry_titles.iter().enumerate() {
                 write_string_to_grid(
-                    &e,
+                    e,
                     &mut content,
                     self.theme_default.fg,
                     self.theme_default.bg,
@@ -824,7 +824,7 @@ impl<T: PartialEq + Debug + Clone + Sync + Send, F: 'static + Sync + Send> Selec
         } else {
             for (i, e) in self.entry_titles.iter().enumerate() {
                 write_string_to_grid(
-                    &format!("[ ] {}", &e),
+                    &format!("[ ] {}", e),
                     &mut content,
                     self.theme_default.fg,
                     self.theme_default.bg,
diff --git a/src/components/utilities/pager.rs b/src/components/utilities/pager.rs
index 601e24ac..9f24543e 100644
--- a/src/components/utilities/pager.rs
+++ b/src/components/utilities/pager.rs
@@ -39,7 +39,6 @@ pub struct Pager {
     colors: ThemeAttribute,
     initialised: bool,
     show_scrollbar: bool,
-    content: CellBuffer,
     filtered_content: Option<(String, Result<CellBuffer>)>,
     text_lines: Vec<String>,
     line_breaker: LineBreakText,
@@ -57,8 +56,10 @@ impl Pager {
     pub const DESCRIPTION: &'static str = "pager";
     const PAGES_AHEAD_TO_RENDER_NO: usize = 16;
     pub fn new(context: &Context) -> Self {
-        let mut ret = Pager::default();
-        ret.minimum_width = context.settings.pager.minimum_width;
+        let mut ret = Pager {
+            minimum_width: context.settings.pager.minimum_width,
+            ..Pager::default()
+        };
         ret.set_colors(crate::conf::value(context, "theme_default"))
             .set_reflow(if context.settings.pager.split_long_lines {
                 Reflow::All
@@ -178,10 +179,7 @@ impl Pager {
                 .stdout(Stdio::piped())
                 .spawn()
                 .chain_err_summary(|| "Failed to start pager filter process")?;
-            let stdin = filter_child
-                .stdin
-                .as_mut()
-                .ok_or_else(|| "failed to open stdin")?;
+            let stdin = filter_child.stdin.as_mut().ok_or("failed to open stdin")?;
             stdin
                 .write_all(text.as_bytes())
                 .chain_err_summary(|| "Failed to write to stdin")?;
@@ -196,7 +194,7 @@ impl Pager {
             for b in out {
                 embedded.process_byte(&mut dev_null, b);
             }
-            Ok(std::mem::replace(embedded.buffer_mut(), Default::default()))
+            Ok(std::mem::take(embedded.buffer_mut()))
         };
         let buf = _f(cmd, &self.text);
         if let Some((width, height)) = buf.as_ref().ok().map(CellBuffer::size) {
@@ -301,7 +299,7 @@ impl Pager {
                 Ok(ref content) => {
                     copy_area(
                         grid,
-                        &content,
+                        content,
                         area,
                         (
                             (
@@ -353,7 +351,7 @@ impl Pager {
                 (upper_left, bottom_right),
                 None,
             );
-            if l.starts_with("⤷") {
+            if l.starts_with('⤷') {
                 grid[upper_left]
                     .set_fg(crate::conf::value(context, "highlight").fg)
                     .set_attrs(crate::conf::value(context, "highlight").attrs);
diff --git a/src/components/utilities/widgets.rs b/src/components/utilities/widgets.rs
index 10e332af..9400a4e2 100644
--- a/src/components/utilities/widgets.rs
+++ b/src/components/utilities/widgets.rs
@@ -42,7 +42,7 @@ impl Default for FormFocus {
 }
 
 pub enum Field {
-    Text(UText, Option<(AutoCompleteFn, AutoComplete)>),
+    Text(UText, Option<(AutoCompleteFn, Box<AutoComplete>)>),
     Choice(Vec<Cow<'static, str>>, Cursor),
 }
 
@@ -456,6 +456,10 @@ impl<T: 'static + std::fmt::Debug + Copy + Default + Send + Sync> FormWidget<T>
         self.layout.len()
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.layout.len() == 0
+    }
+
     pub fn add_button(&mut self, val: (Cow<'static, str>, T)) {
         self.buttons.push(val);
     }
@@ -1003,7 +1007,7 @@ impl Component for AutoComplete {
 }
 
 impl AutoComplete {
-    pub fn new(entries: Vec<AutoCompleteEntry>) -> Self {
+    pub fn new(entries: Vec<AutoCompleteEntry>) -> Box<Self> {
         let mut ret = AutoComplete {
             entries: Vec::new(),
             content: CellBuffer::default(),
@@ -1012,7 +1016,7 @@ impl AutoComplete {
             id: ComponentId::new_v4(),
         };
         ret.set_suggestions(entries);
-        ret
+        Box::new(ret)
     }
 
     pub fn set_suggestions(&mut self, entries: Vec<AutoCompleteEntry>) -> bool {
@@ -1401,7 +1405,7 @@ impl Component for ProgressSpinner {
             if self.active {
                 write_string_to_grid(
                     match self.kind.as_ref() {
-                        Ok(kind) => (Self::KINDS[*kind].1)[self.stage].as_ref(),
+                        Ok(kind) => (Self::KINDS[*kind].1)[self.stage],
                         Err(custom) => custom[self.stage].as_ref(),
                     },
                     grid,
diff --git a/src/conf.rs b/src/conf.rs
index d4eeea10..de75884d 100644
--- a/src/conf.rs
+++ b/src/conf.rs
@@ -250,7 +250,7 @@ impl From<FileAccount> for AccountConf {
         let root_mailbox = x.root_mailbox.clone();
         let identity = x.identity.clone();
         let display_name = x.display_name.clone();
-        let order = x.order.clone();
+        let order = x.order;
         let mailboxes = x
             .mailboxes
             .iter()
@@ -365,13 +365,14 @@ impl FileSettings {
 
     pub fn validate(path: PathBuf, interactive: bool, clear_extras: bool) -> Result<Self> {
         let s = pp::pp(&path)?;
-        let map: toml::map::Map<String, toml::value::Value> = toml::from_str(&s).map_err(|e| {
-            MeliError::new(format!(
-                "{}:\nConfig file is invalid TOML: {}",
-                path.display(),
-                e.to_string()
-            ))
-        })?;
+        let map: toml::map::Map<String, toml::value::Value> =
+            toml::from_str(&s).map_err(|err| {
+                MeliError::new(format!(
+                    "{}:\nConfig file is invalid TOML: {}",
+                    path.display(),
+                    err
+                ))
+            })?;
         /*
          * Check that a global composing option is set and return a user-friendly error message because the
          * default serde one is confusing.
@@ -410,11 +411,11 @@ This is required so that you don't accidentally start meli and find out later th
                 path.display()
             )));
         }
-        let mut s: FileSettings = toml::from_str(&s).map_err(|e| {
+        let mut s: FileSettings = toml::from_str(&s).map_err(|err| {
             MeliError::new(format!(
                 "{}:\nConfig file contains errors: {}",
                 path.display(),
-                e.to_string()
+                err
             ))
         })?;
         let backends = melib::backends::Backends::new();
@@ -831,7 +832,7 @@ mod pp {
                 }
                 i += 1;
             }
-            return Ok(("", None));
+            Ok(("", None))
         }
     }
 
diff --git a/src/conf/accounts.rs b/src/conf/accounts.rs
index 072452dc..2429dcbb 100644
--- a/src/conf/accounts.rs
+++ b/src/conf/accounts.rs
@@ -89,18 +89,11 @@ impl Default for MailboxStatus {
 
 impl MailboxStatus {
     pub fn is_available(&self) -> bool {
-        if let MailboxStatus::Available = self {
-            true
-        } else {
-            false
-        }
+        matches!(self, MailboxStatus::Available)
     }
+
     pub fn is_parsing(&self) -> bool {
-        if let MailboxStatus::Parsing(_, _) = self {
-            true
-        } else {
-            false
-        }
+        matches!(self, MailboxStatus::Parsing(_, _))
     }
 }
 
@@ -132,7 +125,7 @@ impl MailboxEntry {
         if let Some(name) = self.conf.mailbox_conf.alias.as_ref() {
             name
         } else {
-            &self.ref_mailbox.name()
+            self.ref_mailbox.name()
         }
     }
 }
@@ -165,6 +158,7 @@ pub enum JobRequest {
     },
     Fetch {
         mailbox_hash: MailboxHash,
+        #[allow(clippy::type_complexity)]
         handle: JoinHandle<(
             Option<Result<Vec<Envelope>>>,
             Pin<Box<dyn Stream<Item = Result<Vec<Envelope>>> + Send + 'static>>,
@@ -345,26 +339,17 @@ impl core::fmt::Display for JobRequest {
 
 impl JobRequest {
     pub fn is_watch(&self) -> bool {
-        match self {
-            JobRequest::Watch { .. } => true,
-            _ => false,
-        }
+        matches!(self, JobRequest::Watch { .. })
     }
 
     pub fn is_fetch(&self, mailbox_hash: MailboxHash) -> bool {
-        match self {
-            JobRequest::Fetch {
-                mailbox_hash: h, ..
-            } if *h == mailbox_hash => true,
-            _ => false,
-        }
+        matches!(self, JobRequest::Fetch {
+                 mailbox_hash: h, ..
+             } if *h == mailbox_hash)
     }
 
     pub fn is_online(&self) -> bool {
-        match self {
-            JobRequest::IsOnline { .. } => true,
-            _ => false,
-        }
+        matches!(self, JobRequest::IsOnline { .. })
     }
 }
 
@@ -388,7 +373,6 @@ impl Drop for Account {
                 let writer = io::BufWriter::new(f);
                 if let Err(err) = serde_json::to_writer(writer, &self.address_book) {
                     eprintln!("{}", err);
-                    return;
                 };
             };
             /*
@@ -455,7 +439,7 @@ impl Account {
         )?;
 
         let data_dir = xdg::BaseDirectories::with_profile("meli", &name).unwrap();
-        let mut address_book = AddressBook::with_account(&settings.account());
+        let mut address_book = AddressBook::with_account(settings.account());
 
         if let Ok(data) = data_dir.place_data_file("addressbook") {
             if data.exists() {
@@ -730,7 +714,7 @@ impl Account {
                                     format!(
                                         "Failed to update envelope {} in cache: {}",
                                         envelope.message_id_display(),
-                                        err.to_string()
+                                        err
                                     ),
                                     melib::ERROR,
                                 );
@@ -804,7 +788,7 @@ impl Account {
                                         "Failed to update envelope {} in cache: {}",
                                         self.collection.envelopes.read().unwrap()[&env_hash]
                                             .message_id_display(),
-                                        err.to_string()
+                                        err
                                     ),
                                     melib::ERROR,
                                 );
@@ -834,7 +818,7 @@ impl Account {
                                         "Failed to update envelope {} in cache: {}",
                                         &self.collection.envelopes.read().unwrap()[&new_hash]
                                             .message_id_display(),
-                                        err.to_string()
+                                        err
                                     ),
                                     melib::ERROR,
                                 );
@@ -961,7 +945,7 @@ impl Account {
                                     "Failed to remove envelope {} [{}] in cache: {}",
                                     &envelopes[&env_hash].message_id_display(),
                                     env_hash,
-                                    err.to_string()
+                                    err
                                 ),
                                 melib::ERROR,
                             );
@@ -1193,14 +1177,10 @@ impl Account {
             self.special_use_mailbox(SpecialUsageMailbox::Normal),
         ] {
             if let Some(mailbox_hash) = mailbox {
-                if let Err(e) = self.save(bytes, *mailbox_hash, Some(flags)) {
-                    debug!("{:?} could not save msg", e);
+                if let Err(err) = self.save(bytes, *mailbox_hash, Some(flags)) {
+                    debug!("{:?} could not save msg", err);
                     melib::log(
-                        format!(
-                            "Could not save in '{}' mailbox: {}.",
-                            *mailbox_hash,
-                            e.to_string()
-                        ),
+                        format!("Could not save in '{}' mailbox: {}.", *mailbox_hash, err),
                         melib::ERROR,
                     );
                 } else {
@@ -1311,9 +1291,7 @@ impl Account {
                         )
                     };
                     melib::log(&error_message, melib::LoggingLevel::ERROR);
-                    return Err(
-                        MeliError::new(error_message.clone()).set_summary("Message not sent.")
-                    );
+                    return Err(MeliError::new(error_message).set_summary("Message not sent."));
                 }
                 Ok(None)
             }
@@ -1334,11 +1312,11 @@ impl Account {
             }
             SendMail::ServerSubmission => {
                 if self.backend_capabilities.supports_submission {
-                    let job = self.backend.write().unwrap().submit(
-                        message.clone().into_bytes(),
-                        None,
-                        None,
-                    )?;
+                    let job =
+                        self.backend
+                            .write()
+                            .unwrap()
+                            .submit(message.into_bytes(), None, None)?;
 
                     let handle = if self.backend_capabilities.is_async {
                         self.job_executor.spawn_specialized(job)
@@ -1348,8 +1326,8 @@ impl Account {
                     self.insert_job(handle.job_id, JobRequest::SendMessageBackground { handle });
                     return Ok(None);
                 }
-                return Err(MeliError::new("Server does not support submission.")
-                    .set_summary("Message not sent."));
+                Err(MeliError::new("Server does not support submission.")
+                    .set_summary("Message not sent."))
             }
         }
     }
@@ -1400,8 +1378,9 @@ impl Account {
                         )
                             };
                             melib::log(&error_message, melib::LoggingLevel::ERROR);
-                            return Err(MeliError::new(error_message.clone())
-                                .set_summary("Message not sent."));
+                            return Err(
+                                MeliError::new(error_message).set_summary("Message not sent.")
+                            );
                         }
                         Ok(())
                     }
@@ -1423,8 +1402,8 @@ impl Account {
                             fut.await?;
                             return Ok(());
                         }
-                        return Err(MeliError::new("Server does not support submission.")
-                            .set_summary("Message not sent."));
+                        Err(MeliError::new("Server does not support submission.")
+                            .set_summary("Message not sent."))
                     }
                 }
             })
@@ -1537,11 +1516,7 @@ impl Account {
             .mailbox_entries
             .iter()
             .find(|(_, f)| f.conf.mailbox_conf().usage == Some(special_use));
-        if let Some(ret) = ret.as_ref() {
-            Some(ret.1.ref_mailbox.hash())
-        } else {
-            None
-        }
+        ret.as_ref().map(|ret| ret.1.ref_mailbox.hash())
     }
 
     /* Call only in Context::is_online, since only Context can launch the watcher threads if an
@@ -1575,7 +1550,7 @@ impl Account {
                 self.insert_job(handle.job_id, JobRequest::IsOnline { handle });
             }
         }
-        return self.is_online.clone();
+        self.is_online.clone()
     }
 
     pub fn search(
@@ -2272,7 +2247,7 @@ fn build_mailboxes_order(
                 node
             }
 
-            tree.push(rec(*h, &mailbox_entries, 0));
+            tree.push(rec(*h, mailbox_entries, 0));
         }
     }
 
@@ -2356,7 +2331,6 @@ fn build_mailboxes_order(
         fn rec(
             node: &mut MailboxNode,
             mailbox_entries: &IndexMap<MailboxHash, MailboxEntry>,
-            depth: usize,
             mut indentation: u32,
             has_sibling: bool,
         ) {
@@ -2379,16 +2353,10 @@ fn build_mailboxes_order(
             }
             while let Some(i) = iter.next() {
                 let c = &mut node.children[i];
-                rec(
-                    c,
-                    mailbox_entries,
-                    depth + 1,
-                    indentation,
-                    iter.peek() != None,
-                );
+                rec(c, mailbox_entries, indentation, iter.peek() != None);
             }
         }
 
-        rec(node, &mailbox_entries, 1, 0, false);
+        rec(node, mailbox_entries, 0, false);
     }
 }
diff --git a/src/conf/overrides.rs b/src/conf/overrides.rs
index 4ff11a78..581c35e1 100644
--- a/src/conf/overrides.rs
+++ b/src/conf/overrides.rs
@@ -19,7 +19,9 @@
  * along with meli. If not, see <http://www.gnu.org/licenses/>.
  */
 
-//! This module is automatically generated by build.rs.
+#![allow(clippy::derivable_impls)]
+
+//! This module is automatically generated by config_macros.rs.
 use super::*;
 
 #[derive(Debug, Serialize, Deserialize, Clone)]
diff --git a/src/conf/shortcuts.rs b/src/conf/shortcuts.rs
index d0b294e5..50875b3f 100644
--- a/src/conf/shortcuts.rs
+++ b/src/conf/shortcuts.rs
@@ -34,7 +34,7 @@ macro_rules! shortcut {
     };
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
+#[derive(Default, Debug, Clone, Serialize, Deserialize)]
 #[serde(deny_unknown_fields)]
 pub struct Shortcuts {
     #[serde(default)]
@@ -55,21 +55,6 @@ pub struct Shortcuts {
     pub pager: PagerShortcuts,
 }
 
-impl Default for Shortcuts {
-    fn default() -> Self {
-        Self {
-            general: GeneralShortcuts::default(),
-            listing: ListingShortcuts::default(),
-            composing: ComposingShortcuts::default(),
-            compact_listing: CompactListingShortcuts::default(),
-            contact_list: ContactListShortcuts::default(),
-            envelope_view: EnvelopeViewShortcuts::default(),
-            thread_view: ThreadViewShortcuts::default(),
-            pager: PagerShortcuts::default(),
-        }
-    }
-}
-
 impl DotAddressable for Shortcuts {
     fn lookup(&self, parent_field: &str, path: &[&str]) -> Result<String> {
         match path.first() {
diff --git a/src/conf/tags.rs b/src/conf/tags.rs
index 42f94be0..9f75a222 100644
--- a/src/conf/tags.rs
+++ b/src/conf/tags.rs
@@ -28,7 +28,7 @@ use serde::{Deserialize, Deserializer};
 use std::collections::{hash_map::DefaultHasher, HashMap, HashSet};
 use std::hash::Hasher;
 
-#[derive(Debug, Deserialize, Clone, Serialize)]
+#[derive(Default, Debug, Deserialize, Clone, Serialize)]
 #[serde(deny_unknown_fields)]
 pub struct TagsSettings {
     #[serde(default, deserialize_with = "tag_color_de")]
@@ -37,15 +37,6 @@ pub struct TagsSettings {
     pub ignore_tags: HashSet<u64>,
 }
 
-impl Default for TagsSettings {
-    fn default() -> Self {
-        TagsSettings {
-            colors: Default::default(),
-            ignore_tags: Default::default(),
-        }
-    }
-}
-
 pub fn tag_set_de<'de, D, T: std::convert::From<HashSet<u64>>>(
     deserializer: D,
 ) -> std::result::Result<T, D::Error>
diff --git a/src/conf/themes.rs b/src/conf/themes.rs
index 73d9fcaa..315c1bce 100644
--- a/src/conf/themes.rs
+++ b/src/conf/themes.rs
@@ -102,7 +102,7 @@ pub fn attrs(context: &Context, key: &'static str) -> Attr {
 }
 
 #[inline(always)]
-fn unlink<'k, 't: 'k>(theme: &'t Theme, key: &'k Cow<'static, str>) -> ThemeAttribute {
+fn unlink<'k, 't: 'k>(theme: &'t Theme, key: &'k str) -> ThemeAttribute {
     ThemeAttribute {
         fg: unlink_fg(theme, &ColorField::Fg, key),
         bg: unlink_bg(theme, &ColorField::Bg, key),
@@ -111,11 +111,7 @@ fn unlink<'k, 't: 'k>(theme: &'t Theme, key: &'k Cow<'static, str>) -> ThemeAttr
 }
 
 #[inline(always)]
-fn unlink_fg<'k, 't: 'k>(
-    theme: &'t Theme,
-    mut field: &'k ColorField,
-    mut key: &'k Cow<'static, str>,
-) -> Color {
+fn unlink_fg<'k, 't: 'k>(theme: &'t Theme, mut field: &'k ColorField, mut key: &'k str) -> Color {
     loop {
         match field {
             ColorField::LikeSelf | ColorField::Fg => match &theme[key].fg {
@@ -166,11 +162,7 @@ fn unlink_fg<'k, 't: 'k>(
 }
 
 #[inline(always)]
-fn unlink_bg<'k, 't: 'k>(
-    theme: &'t Theme,
-    mut field: &'k ColorField,
-    mut key: &'k Cow<'static, str>,
-) -> Color {
+fn unlink_bg<'k, 't: 'k>(theme: &'t Theme, mut field: &'k ColorField, mut key: &'k str) -> Color {
     loop {
         match field {
             ColorField::LikeSelf | ColorField::Bg => match &theme[key].bg {
@@ -220,7 +212,7 @@ fn unlink_bg<'k, 't: 'k>(
 }
 
 #[inline(always)]
-fn unlink_attrs<'k, 't: 'k>(theme: &'t Theme, mut key: &'k Cow<'static, str>) -> Attr {
+fn unlink_attrs<'k, 't: 'k>(theme: &'t Theme, mut key: &'k str) -> Attr {
     loop {
         match &theme[key].attrs {
             ThemeValue::Link(ref new_key, ()) => key = new_key,
@@ -416,8 +408,8 @@ impl<'de> Deserialize<'de> for ThemeValue<Attr> {
         D: Deserializer<'de>,
     {
         if let Ok(s) = <String>::deserialize(deserializer) {
-            if s.starts_with("$") {
-                Ok(ThemeValue::Alias(s[1..].to_string().into()))
+            if let Some(stripped) = s.strip_prefix('$') {
+                Ok(ThemeValue::Alias(stripped.to_string().into()))
             } else if let Ok(c) = Attr::from_string_de::<'de, D, String>(s.clone()) {
                 Ok(ThemeValue::Value(c))
             } else {
@@ -467,8 +459,8 @@ impl<'de> Deserialize<'de> for ThemeValue<Color> {
         D: Deserializer<'de>,
     {
         if let Ok(s) = <String>::deserialize(deserializer) {
-            if s.starts_with("$") {
-                Ok(ThemeValue::Alias(s[1..].to_string().into()))
+            if let Some(stripped) = s.strip_prefix('$') {
+                Ok(ThemeValue::Alias(stripped.to_string().into()))
             } else if let Ok(c) = Color::from_string_de::<'de, D>(s.clone()) {
                 Ok(ThemeValue::Value(c))
             } else if s.ends_with(".fg") {
@@ -606,37 +598,26 @@ mod regexp {
 
         fn next(&mut self) -> Option<Self::Item> {
             loop {
-                let next_byte_offset = self.pcre_iter.next();
-                if next_byte_offset.is_none() {
-                    return None;
-                }
-                let next_byte_offset = next_byte_offset.unwrap();
+                let next_byte_offset = self.pcre_iter.next()?;
                 if next_byte_offset.is_err() {
                     continue;
                 }
                 let next_byte_offset = next_byte_offset.unwrap();
 
-                let mut next_char_index = self.char_indices.next();
-                if next_char_index.is_none() {
-                    return None;
-                }
+                let mut next_char_index = self.char_indices.next()?;
 
-                while next_byte_offset.start() < next_char_index.unwrap().0 {
+                while next_byte_offset.start() < next_char_index.0 {
                     self.char_offset += 1;
-                    next_char_index = self.char_indices.next();
-                    if next_char_index.is_none() {
-                        return None;
-                    }
+                    next_char_index = self.char_indices.next()?;
                 }
                 let start = self.char_offset;
 
                 while next_byte_offset.end()
-                    >= self
+                    > self
                         .char_indices
                         .next()
                         .map(|(v, _)| v)
-                        .unwrap_or(next_byte_offset.end())
-                        + 1
+                        .unwrap_or_else(|| next_byte_offset.end())
                 {
                     self.char_offset += 1;
                 }
@@ -1219,7 +1200,7 @@ impl Themes {
         Ok(())
     }
     pub fn validate(&self) -> Result<()> {
-        let hash_set: HashSet<&'static str> = DEFAULT_KEYS.into_iter().map(|k| *k).collect();
+        let hash_set: HashSet<&'static str> = DEFAULT_KEYS.iter().copied().collect();
         Themes::validate_keys("light", &self.light, &hash_set)?;
         Themes::validate_keys("dark", &self.dark, &hash_set)?;
         for (name, t) in self.other_themes.iter() {
@@ -1255,51 +1236,49 @@ impl Themes {
             t => self.other_themes.get(t).unwrap_or(&self.dark),
         };
         let mut ret = String::new();
-        ret.extend(format!("[terminal.themes.{}]\n", key).chars());
+        ret.push_str(&format!("[terminal.themes.{}]\n", key));
         if unlink {
             for k in theme.keys() {
-                ret.extend(
-                    format!(
-                        "\"{}\" = {{ fg = {}, bg = {}, attrs = {} }}\n",
-                        k,
-                        toml::to_string(&unlink_fg(&theme, &ColorField::Fg, k)).unwrap(),
-                        toml::to_string(&unlink_bg(&theme, &ColorField::Bg, k)).unwrap(),
-                        toml::to_string(&unlink_attrs(&theme, k)).unwrap(),
-                    )
-                    .chars(),
-                );
+                ret.push_str(&format!(
+                    "\"{}\" = {{ fg = {}, bg = {}, attrs = {} }}\n",
+                    k,
+                    toml::to_string(&unlink_fg(theme, &ColorField::Fg, k)).unwrap(),
+                    toml::to_string(&unlink_bg(theme, &ColorField::Bg, k)).unwrap(),
+                    toml::to_string(&unlink_attrs(theme, k)).unwrap(),
+                ));
             }
         } else {
             for k in theme.keys() {
-                ret.extend(
-                    format!(
-                        "\"{}\" = {{ fg = {}, bg = {}, attrs = {} }}\n",
-                        k,
-                        toml::to_string(&theme[k].fg).unwrap(),
-                        toml::to_string(&theme[k].bg).unwrap(),
-                        toml::to_string(&theme[k].attrs).unwrap(),
-                    )
-                    .chars(),
-                );
+                ret.push_str(&format!(
+                    "\"{}\" = {{ fg = {}, bg = {}, attrs = {} }}\n",
+                    k,
+                    toml::to_string(&theme[k].fg).unwrap(),
+                    toml::to_string(&theme[k].bg).unwrap(),
+                    toml::to_string(&theme[k].attrs).unwrap(),
+                ));
             }
         }
         ret
     }
-    pub fn to_string(&self) -> String {
-        let mut ret = String::new();
-        ret.extend(self.key_to_string("dark", true).chars());
-
-        ret.push_str("\n\n");
-        ret.extend(self.key_to_string("light", true).chars());
-        for name in self.other_themes.keys() {
-            ret.push_str("\n\n");
-            ret.extend(self.key_to_string(name, true).chars());
-        }
-        ret
-    }
+}
+
+impl std::fmt::Display for Themes {
+    fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
+        let mut ret = String::new();
+        ret.push_str(&self.key_to_string("dark", true));
+
+        ret.push_str("\n\n");
+        ret.push_str(&self.key_to_string("light", true));
+        for name in self.other_themes.keys() {
+            ret.push_str("\n\n");
+            ret.push_str(&self.key_to_string(name, true));
+        }
+        write!(fmt, "{}", ret)
+    }
 }
 
 impl Default for Themes {
+    #[allow(clippy::needless_update)]
     fn default() -> Themes {
         let mut light = IndexMap::default();
         let mut dark = IndexMap::default();
@@ -1762,9 +1741,9 @@ impl Serialize for Themes {
                 new_map.insert(
                     k.clone(),
                     ThemeAttribute {
-                        fg: unlink_fg(&t, &ColorField::Fg, k),
-                        bg: unlink_bg(&t, &ColorField::Bg, k),
-                        attrs: unlink_attrs(&t, k),
+                        fg: unlink_fg(t, &ColorField::Fg, k),
+                        bg: unlink_bg(t, &ColorField::Bg, k),
+                        attrs: unlink_attrs(t, k),
                     },
                 );
             }
@@ -1790,10 +1769,10 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
     }
     fn is_cyclic_util<'a>(
         course: Course,
-        k: &'a Cow<'static, str>,
-        visited: &mut IndexMap<(&'a Cow<'static, str>, Course), bool>,
-        stack: &mut IndexMap<(&'a Cow<'static, str>, Course), bool>,
-        path: &mut SmallVec<[(&'a Cow<'static, str>, Course); 16]>,
+        k: &'a str,
+        visited: &mut IndexMap<(&'a str, Course), bool>,
+        stack: &mut IndexMap<(&'a str, Course), bool>,
+        path: &mut SmallVec<[(&'a str, Course); 16]>,
         theme: &'a Theme,
     ) -> bool {
         if !visited[&(k, course)] {
@@ -1804,6 +1783,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                 Course::Fg => match theme[k].fg {
                     ThemeValue::Link(ref l, ColorField::LikeSelf)
                     | ThemeValue::Link(ref l, ColorField::Fg) => {
+                        let l = l.as_ref();
                         path.push((l, Course::Fg));
                         if (!visited[&(l, Course::Fg)]
                             && is_cyclic_util(course, l, visited, stack, path, theme))
@@ -1814,6 +1794,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Link(ref l, ColorField::Bg) => {
+                        let l = l.as_ref();
                         path.push((l, Course::Bg));
                         if (!visited[&(l, Course::Bg)]
                             && is_cyclic_util(Course::Bg, l, visited, stack, path, theme))
@@ -1824,6 +1805,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Alias(ref ident) => {
+                        let ident = ident.as_ref();
                         path.push((ident, Course::ColorAliasFg));
                         if (!visited[&(ident, Course::ColorAliasFg)]
                             && is_cyclic_util(
@@ -1845,6 +1827,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                 Course::Bg => match theme[k].bg {
                     ThemeValue::Link(ref l, ColorField::LikeSelf)
                     | ThemeValue::Link(ref l, ColorField::Bg) => {
+                        let l = l.as_ref();
                         path.push((l, Course::Bg));
                         if (!visited[&(l, Course::Bg)]
                             && is_cyclic_util(Course::Bg, l, visited, stack, path, theme))
@@ -1855,6 +1838,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Link(ref l, ColorField::Fg) => {
+                        let l = l.as_ref();
                         path.push((l, Course::Fg));
                         if (!visited[&(l, Course::Fg)]
                             && is_cyclic_util(Course::Fg, l, visited, stack, path, theme))
@@ -1865,6 +1849,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Alias(ref ident) => {
+                        let ident = ident.as_ref();
                         path.push((ident, Course::ColorAliasBg));
                         if (!visited[&(ident, Course::ColorAliasBg)]
                             && is_cyclic_util(
@@ -1885,6 +1870,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                 },
                 Course::Attrs => match theme[k].attrs {
                     ThemeValue::Link(ref l, _) => {
+                        let l = l.as_ref();
                         path.push((l, course));
                         if (!visited[&(l, course)]
                             && is_cyclic_util(course, l, visited, stack, path, theme))
@@ -1895,6 +1881,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Alias(ref ident) => {
+                        let ident = ident.as_ref();
                         path.push((ident, Course::AttrAlias));
                         if (!visited[&(ident, Course::AttrAlias)]
                             && is_cyclic_util(
@@ -1915,6 +1902,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                 },
                 Course::ColorAliasFg | Course::ColorAliasBg => match &theme.color_aliases[k] {
                     ThemeValue::Link(ref l, ref field) => {
+                        let l = l.as_ref();
                         let course = match (course, field) {
                             (Course::ColorAliasFg, ColorField::LikeSelf) => Course::Fg,
                             (Course::ColorAliasBg, ColorField::LikeSelf) => Course::Bg,
@@ -1934,6 +1922,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Alias(ref ident) => {
+                        let ident = ident.as_ref();
                         path.push((ident, course));
                         if (!visited[&(ident, course)]
                             && is_cyclic_util(course, ident, visited, stack, path, theme))
@@ -1947,6 +1936,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                 },
                 Course::AttrAlias => match &theme.attr_aliases[k] {
                     ThemeValue::Link(ref l, ()) => {
+                        let l = l.as_ref();
                         path.push((l, Course::Attrs));
                         if (!visited[&(l, Course::Attrs)]
                             && is_cyclic_util(Course::Attrs, l, visited, stack, path, theme))
@@ -1957,6 +1947,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
                         path.pop();
                     }
                     ThemeValue::Alias(ref ident) => {
+                        let ident = ident.as_ref();
                         path.push((ident, course));
                         if (!visited[&(ident, course)]
                             && is_cyclic_util(course, ident, visited, stack, path, theme))
@@ -1977,35 +1968,28 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
     let mut path = SmallVec::new();
     let mut visited = theme
         .keys()
-        .map(|k| {
-            std::iter::once(((k, Course::Fg), false))
-                .chain(std::iter::once(((k, Course::Bg), false)))
-                .chain(std::iter::once(((k, Course::Attrs), false)))
+        .flat_map(|k| {
+            std::iter::once(((k.as_ref(), Course::Fg), false))
+                .chain(std::iter::once(((k.as_ref(), Course::Bg), false)))
+                .chain(std::iter::once(((k.as_ref(), Course::Attrs), false)))
         })
-        .flatten()
-        .chain(
-            theme
-                .color_aliases
-                .keys()
-                .map(|k| {
-                    std::iter::once(((k, Course::ColorAliasFg), false))
-                        .chain(std::iter::once(((k, Course::ColorAliasBg), false)))
-                })
-                .flatten(),
-        )
+        .chain(theme.color_aliases.keys().flat_map(|k| {
+            std::iter::once(((k.as_ref(), Course::ColorAliasFg), false))
+                .chain(std::iter::once(((k.as_ref(), Course::ColorAliasBg), false)))
+        }))
         .chain(
             theme
                 .attr_aliases
                 .keys()
-                .map(|k| ((k, Course::AttrAlias), false)),
+                .map(|k| ((k.as_ref(), Course::AttrAlias), false)),
         )
-        .collect::<IndexMap<(&Cow<'static, str>, Course), bool>>();
+        .collect::<IndexMap<(&str, Course), bool>>();
 
     let mut stack = visited.clone();
     for k in theme.keys() {
         for &course in [Course::Fg, Course::Bg, Course::Attrs].iter() {
-            path.push((k, course));
-            if is_cyclic_util(course, k, &mut visited, &mut stack, &mut path, &theme) {
+            path.push((k.as_ref(), course));
+            if is_cyclic_util(course, k, &mut visited, &mut stack, &mut path, theme) {
                 let path = path
                     .into_iter()
                     .map(|(k, c)| match c {
@@ -2037,7 +2021,7 @@ fn is_cyclic(theme: &Theme) -> std::result::Result<(), String> {
         }
     }
 
-    return Ok(());
+    Ok(())
 }
 
 #[test]
diff --git a/src/mailcap.rs b/src/mailcap.rs
index 745945d3..7ff0e824 100644
--- a/src/mailcap.rs
+++ b/src/mailcap.rs
@@ -96,6 +96,7 @@ impl MailcapEntry {
                 //let flags = parts_iter.next().unwrap();
                 if key.starts_with(&content_type) || key.matches_glob(&content_type) {
                     let mut copiousoutput = false;
+                    #[allow(clippy::while_let_on_iterator)]
                     while let Some(flag) = parts_iter.next() {
                         if flag.trim() == "copiousoutput" {
                             copiousoutput = true;
@@ -118,6 +119,7 @@ impl MailcapEntry {
                 //let flags = parts_iter.next().unwrap();
                 if key.starts_with(&content_type) || key.matches_glob(&content_type) {
                     let mut copiousoutput = false;
+                    #[allow(clippy::while_let_on_iterator)]
                     while let Some(flag) = parts_iter.next() {
                         if flag.trim() == "copiousoutput" {
                             copiousoutput = true;
@@ -178,7 +180,7 @@ impl MailcapEntry {
                     .collect::<Vec<String>>();
                 let cmd_string = format!("{} {}", cmd, args.join(" "));
                 melib::log(
-                    format!("Executing: sh -c \"{}\"", cmd_string.replace("\"", "\\\"")),
+                    format!("Executing: sh -c \"{}\"", cmd_string.replace('"', "\\\"")),
                     melib::DEBUG,
                 );
                 if copiousoutput {
@@ -212,25 +214,23 @@ impl MailcapEntry {
                         .spawn()?;
                     pager.stdin.as_mut().unwrap().write_all(&out)?;
                     debug!(pager.wait_with_output()?.stdout);
+                } else if needs_stdin {
+                    let mut child = Command::new("sh")
+                        .args(&["-c", &cmd_string])
+                        .stdin(Stdio::piped())
+                        .stdout(Stdio::inherit())
+                        .spawn()?;
+
+                    child.stdin.as_mut().unwrap().write_all(&decode(a, None))?;
+                    debug!(child.wait_with_output()?.stdout);
                 } else {
-                    if needs_stdin {
-                        let mut child = Command::new("sh")
-                            .args(&["-c", &cmd_string])
-                            .stdin(Stdio::piped())
-                            .stdout(Stdio::inherit())
-                            .spawn()?;
+                    let child = Command::new("sh")
+                        .args(&["-c", &cmd_string])
+                        .stdin(Stdio::inherit())
+                        .stdout(Stdio::inherit())
+                        .spawn()?;
 
-                        child.stdin.as_mut().unwrap().write_all(&decode(a, None))?;
-                        debug!(child.wait_with_output()?.stdout);
-                    } else {
-                        let child = Command::new("sh")
-                            .args(&["-c", &cmd_string])
-                            .stdin(Stdio::inherit())
-                            .stdout(Stdio::inherit())
-                            .spawn()?;
-
-                        debug!(child.wait_with_output()?.stdout);
-                    }
+                    debug!(child.wait_with_output()?.stdout);
                 }
                 context.replies.push_back(UIEvent::Fork(ForkType::Finished));
                 Ok(())
diff --git a/src/sqlite3.rs b/src/sqlite3.rs
index a9ebd526..c2ad9659 100644
--- a/src/sqlite3.rs
+++ b/src/sqlite3.rs
@@ -168,14 +168,14 @@ pub async fn insert(
                 format!(
                     "Failed to open envelope {}: {}",
                     envelope.message_id_display(),
-                    err.to_string()
+                    err
                 )
             );
             log(
                 format!(
                     "Failed to open envelope {}: {}",
                     envelope.message_id_display(),
-                    err.to_string()
+                    err
                 ),
                 ERROR,
             );
@@ -190,13 +190,13 @@ pub async fn insert(
         debug!(
             "Failed to insert envelope {}: {}",
             envelope.message_id_display(),
-            err.to_string()
+            err
         );
         log(
             format!(
                 "Failed to insert envelope {}: {}",
                 envelope.message_id_display(),
-                err.to_string()
+                err
             ),
             ERROR,
         );
@@ -217,19 +217,19 @@ pub async fn insert(
     if let Err(err) = conn.execute(
             "INSERT OR REPLACE INTO envelopes (account_id, hash, date, _from, _to, cc, bcc, subject, message_id, in_reply_to, _references, flags, has_attachments, body_text, timestamp)
               VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15)",
-              params![account_id, envelope.hash().to_be_bytes().to_vec(), envelope.date_as_str(), envelope.field_from_to_string(), envelope.field_to_to_string(), envelope.field_cc_to_string(), envelope.field_bcc_to_string(), envelope.subject().into_owned().trim_end_matches('\u{0}'), envelope.message_id_display().to_string(), envelope.in_reply_to_display().map(|f| f.to_string()).unwrap_or(String::new()), envelope.field_references_to_string(), i64::from(envelope.flags().bits()), if envelope.has_attachments() { 1 } else { 0 }, body, envelope.date().to_be_bytes().to_vec()],
+              params![account_id, envelope.hash().to_be_bytes().to_vec(), envelope.date_as_str(), envelope.field_from_to_string(), envelope.field_to_to_string(), envelope.field_cc_to_string(), envelope.field_bcc_to_string(), envelope.subject().into_owned().trim_end_matches('\u{0}'), envelope.message_id_display().to_string(), envelope.in_reply_to_display().map(|f| f.to_string()).unwrap_or_default(), envelope.field_references_to_string(), i64::from(envelope.flags().bits()), if envelope.has_attachments() { 1 } else { 0 }, body, envelope.date().to_be_bytes().to_vec()],
         )
             .map_err(|e| MeliError::new(e.to_string())) {
                 debug!(
                         "Failed to insert envelope {}: {}",
                         envelope.message_id_display(),
-                        err.to_string()
+                        err
                     );
                 log(
                     format!(
                         "Failed to insert envelope {}: {}",
                         envelope.message_id_display(),
-                        err.to_string()
+                        err
                     ),
                     ERROR,
                 );
@@ -253,17 +253,9 @@ pub fn remove(env_hash: EnvelopeHash) -> Result<()> {
         )
         .map_err(|e| MeliError::new(e.to_string()))
     {
-        debug!(
-            "Failed to remove envelope {}: {}",
-            env_hash,
-            err.to_string()
-        );
+        debug!("Failed to remove envelope {}: {}", env_hash, err);
         log(
-            format!(
-                "Failed to remove envelope {}: {}",
-                env_hash,
-                err.to_string()
-            ),
+            format!("Failed to remove envelope {}: {}", env_hash, err),
             ERROR,
         );
         return Err(err);
@@ -324,11 +316,11 @@ pub fn index(context: &mut crate::state::Context, account_index: usize) -> Resul
                     .await
                     .chain_err_summary(|| format!("Failed to open envelope {}", env_hash))?;
                 let envelopes_lck = acc_mutex.read().unwrap();
-                if let Some(e) = envelopes_lck.get(&env_hash) {
+                if let Some(e) = envelopes_lck.get(env_hash) {
                     let body = e.body_bytes(&bytes).text().replace('\0', "");
                     conn.execute("INSERT OR REPLACE INTO envelopes (account_id, hash, date, _from, _to, cc, bcc, subject, message_id, in_reply_to, _references, flags, has_attachments, body_text, timestamp)
               VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15)",
-              params![account_id, e.hash().to_be_bytes().to_vec(), e.date_as_str(), e.field_from_to_string(), e.field_to_to_string(), e.field_cc_to_string(), e.field_bcc_to_string(), e.subject().into_owned().trim_end_matches('\u{0}'), e.message_id_display().to_string(), e.in_reply_to_display().map(|f| f.to_string()).unwrap_or(String::new()), e.field_references_to_string(), i64::from(e.flags().bits()), if e.has_attachments() { 1 } else { 0 }, body, e.date().to_be_bytes().to_vec()],
+              params![account_id, e.hash().to_be_bytes().to_vec(), e.date_as_str(), e.field_from_to_string(), e.field_to_to_string(), e.field_cc_to_string(), e.field_bcc_to_string(), e.subject().into_owned().trim_end_matches('\u{0}'), e.message_id_display().to_string(), e.in_reply_to_display().map(|f| f.to_string()).unwrap_or_default(), e.field_references_to_string(), i64::from(e.flags().bits()), if e.has_attachments() { 1 } else { 0 }, body, e.date().to_be_bytes().to_vec()],
                         ).chain_err_summary(|| format!( "Failed to insert envelope {}", e.message_id_display()))?;
                 }
             }
@@ -366,7 +358,7 @@ pub fn search(
         .prepare(
             debug!(format!(
                 "SELECT hash FROM envelopes WHERE {} ORDER BY {} {};",
-                query_to_sql(&query),
+                query_to_sql(query),
                 sort_field,
                 sort_order
             ))
@@ -375,7 +367,7 @@ pub fn search(
         .map_err(|e| MeliError::new(e.to_string()))?;
 
     let results = stmt
-        .query_map([], |row| Ok(row.get(0)?))
+        .query_map([], |row| row.get(0))
         .map_err(|e| MeliError::new(e.to_string()))?
         .map(|r: std::result::Result<Vec<u8>, rusqlite::Error>| {
             Ok(u64::from_be_bytes(
@@ -424,14 +416,14 @@ pub fn query_to_sql(q: &Query) -> String {
                 s.push_str("%\" ");
             }
             And(q1, q2) => {
-                s.push_str("(");
+                s.push('(');
                 rec(q1, s);
                 s.push_str(") AND (");
                 rec(q2, s);
                 s.push_str(") ");
             }
             Or(q1, q2) => {
-                s.push_str("(");
+                s.push('(');
                 rec(q1, s);
                 s.push_str(") OR (");
                 rec(q2, s);
@@ -445,7 +437,7 @@ pub fn query_to_sql(q: &Query) -> String {
             Flags(v) => {
                 let total = v.len();
                 if total > 1 {
-                    s.push_str("(");
+                    s.push('(');
                 }
                 for (i, f) in v.iter().enumerate() {
                     match f.as_str() {
diff --git a/src/state.rs b/src/state.rs
index b58d3c1f..146a6ce1 100644
--- a/src/state.rs
+++ b/src/state.rs
@@ -134,20 +134,18 @@ impl Context {
         } = self;
         let was_online = accounts[account_pos].is_online.is_ok();
         let ret = accounts[account_pos].is_online();
-        if ret.is_ok() {
-            if !was_online {
-                debug!("inserting mailbox hashes:");
-                for mailbox_node in accounts[account_pos].list_mailboxes() {
-                    debug!(
-                        "hash & mailbox: {:?} {}",
-                        mailbox_node.hash,
-                        accounts[account_pos][&mailbox_node.hash].name()
-                    );
-                }
-                accounts[account_pos].watch();
-
-                replies.push_back(UIEvent::AccountStatusChange(accounts[account_pos].hash()));
+        if ret.is_ok() && !was_online {
+            debug!("inserting mailbox hashes:");
+            for mailbox_node in accounts[account_pos].list_mailboxes() {
+                debug!(
+                    "hash & mailbox: {:?} {}",
+                    mailbox_node.hash,
+                    accounts[account_pos][&mailbox_node.hash].name()
+                );
             }
+            accounts[account_pos].watch();
+
+            replies.push_back(UIEvent::AccountStatusChange(accounts[account_pos].hash()));
         }
         if ret.is_ok() != was_online {
             replies.push_back(UIEvent::AccountStatusChange(accounts[account_pos].hash()));
@@ -331,7 +329,7 @@ impl State {
             display_messages_area: ((0, 0), (0, 0)),
             context: Context {
                 accounts,
-                settings: settings,
+                settings,
                 dirty_areas: VecDeque::with_capacity(5),
                 replies: VecDeque::with_capacity(5),
                 temp_files: Vec::new(),
@@ -399,10 +397,8 @@ impl State {
                 }
                 self.rcv_event(notification);
             }
-        } else {
-            if let melib::backends::RefreshEventKind::Failure(err) = event.kind {
-                debug!(err);
-            }
+        } else if let melib::backends::RefreshEventKind::Failure(err) = event.kind {
+            debug!(err);
         }
     }
 
@@ -850,7 +846,7 @@ impl State {
                 ));
             }
             AccountAction(ref account_name, PrintAccountSetting(ref setting)) => {
-                let path = setting.split(".").collect::<SmallVec<[&str; 16]>>();
+                let path = setting.split('.').collect::<SmallVec<[&str; 16]>>();
                 if let Some(pos) = self
                     .context
                     .accounts
@@ -858,13 +854,12 @@ impl State {
                     .position(|(_h, a)| a.name() == account_name)
                 {
                     self.context.replies.push_back(UIEvent::StatusEvent(
-                        StatusEvent::UpdateStatus(format!(
-                            "{}",
+                        StatusEvent::UpdateStatus(
                             self.context.accounts[pos]
                                 .settings
                                 .lookup("settings", &path)
-                                .unwrap_or_else(|err| err.to_string())
-                        )),
+                                .unwrap_or_else(|err| err.to_string()),
+                        ),
                     ));
                 } else {
                     self.context.replies.push_back(UIEvent::Notification(
@@ -872,20 +867,18 @@ impl State {
                         format!("Account {} was not found.", account_name),
                         Some(NotificationType::Error(ErrorKind::None)),
                     ));
-                    return;
                 }
             }
             PrintSetting(ref setting) => {
-                let path = setting.split(".").collect::<SmallVec<[&str; 16]>>();
+                let path = setting.split('.').collect::<SmallVec<[&str; 16]>>();
                 self.context
                     .replies
-                    .push_back(UIEvent::StatusEvent(StatusEvent::UpdateStatus(format!(
-                        "{}",
+                    .push_back(UIEvent::StatusEvent(StatusEvent::UpdateStatus(
                         self.context
                             .settings
                             .lookup("settings", &path)
-                            .unwrap_or_else(|err| err.to_string())
-                    ))));
+                            .unwrap_or_else(|err| err.to_string()),
+                    )));
             }
             ToggleMouse => {
                 self.screen.mouse = !self.screen.mouse;
@@ -920,7 +913,7 @@ impl State {
         match event {
             // Command type is handled only by State.
             UIEvent::Command(cmd) => {
-                if let Ok(action) = parse_command(&cmd.as_bytes()) {
+                if let Ok(action) = parse_command(cmd.as_bytes()) {
                     if action.needs_confirmation() {
                         self.overlay.push(Box::new(UIConfirmationDialog::new(
                             "You sure?",
@@ -932,7 +925,7 @@ impl State {
                                     Box::new(if result { Some(action) } else { None }),
                                 ))
                             })),
-                            &mut self.context,
+                            &self.context,
                         )));
                     } else if let Action::ReloadConfiguration = action {
                         match Settings::new().and_then(|new_settings| {
@@ -952,7 +945,7 @@ impl State {
                             Ok(new_settings)
                         }) {
                             Ok(new_settings) => {
-                                let old_settings = std::mem::replace(&mut self.context.settings, new_settings);
+                                let old_settings = Box::new(std::mem::replace(&mut self.context.settings, new_settings));
                                 self.context.replies.push_back(UIEvent::ConfigReload {
                                     old_settings
                                 });
@@ -1130,11 +1123,8 @@ impl State {
                 match w {
                     Ok(Some(_)) => true,
                     Ok(None) => false,
-                    Err(e) => {
-                        log(
-                            format!("Failed to wait on editor process: {}", e.to_string()),
-                            ERROR,
-                        );
+                    Err(err) => {
+                        log(format!("Failed to wait on editor process: {}", err), ERROR);
                         return None;
                     }
                 }
@@ -1144,11 +1134,8 @@ impl State {
                 match w {
                     Ok(Some(_)) => true,
                     Ok(None) => false,
-                    Err(e) => {
-                        log(
-                            format!("Failed to wait on child process: {}", e.to_string()),
-                            ERROR,
-                        );
+                    Err(err) => {
+                        log(format!("Failed to wait on child process: {}", err), ERROR);
                         return None;
                     }
                 }
@@ -1174,7 +1161,7 @@ impl State {
     }
 
     pub fn switch_to_alternate_screen(&mut self) {
-        self.screen.switch_to_alternate_screen(&mut self.context);
+        self.screen.switch_to_alternate_screen(&self.context);
     }
 
     fn flush(&mut self) {
diff --git a/src/terminal/cells.rs b/src/terminal/cells.rs
index a7ce43d8..ba739a62 100644
--- a/src/terminal/cells.rs
+++ b/src/terminal/cells.rs
@@ -151,7 +151,7 @@ impl CellBuffer {
     pub fn resize(&mut self, newcols: usize, newrows: usize, blank: Option<Cell>) -> bool {
         let newlen = newcols * newrows;
         if (self.cols, self.rows) == (newcols, newrows) || newlen >= Self::MAX_SIZE {
-            return !(newlen >= Self::MAX_SIZE);
+            return newlen < Self::MAX_SIZE;
         }
 
         let blank = blank.unwrap_or(self.default_cell);
@@ -432,10 +432,10 @@ impl CellBuffer {
     pub fn set_tag(&mut self, tag: u64, start: (usize, usize), end: (usize, usize)) {
         let start = self
             .pos_to_index(start.0, start.1)
-            .unwrap_or(self.buf.len().saturating_sub(1));
+            .unwrap_or_else(|| self.buf.len().saturating_sub(1));
         let end = self
             .pos_to_index(end.0, end.1)
-            .unwrap_or(self.buf.len().saturating_sub(1));
+            .unwrap_or_else(|| self.buf.len().saturating_sub(1));
         if start != end {
             self.tag_associations.push((tag, (start, end)));
         }
@@ -856,9 +856,9 @@ impl Attr {
             "Blink" => Ok(Attr::BLINK),
             "Reverse" => Ok(Attr::REVERSE),
             "Hidden" => Ok(Attr::HIDDEN),
-            combination if combination.contains("|") => {
+            combination if combination.contains('|') => {
                 let mut ret = Attr::DEFAULT;
-                for c in combination.trim().split("|") {
+                for c in combination.trim().split('|') {
                     ret |= Self::from_string_de::<'de, D, &str>(c)?;
                 }
                 Ok(ret)
@@ -1725,7 +1725,7 @@ impl core::cmp::Ord for FormatTag {
 
 impl core::cmp::PartialOrd for FormatTag {
     fn partial_cmp(&self, other: &Self) -> Option<core::cmp::Ordering> {
-        Some(self.cmp(&other))
+        Some(self.cmp(other))
     }
 }
 
diff --git a/src/terminal/color.rs b/src/terminal/color.rs
index d65671a7..872394d9 100644
--- a/src/terminal/color.rs
+++ b/src/terminal/color.rs
@@ -391,10 +391,12 @@ impl Color {
             "Yellow5" => 106,
             "Yellow6" => 148,
             "Default" => return Ok(Color::Default),
-            s if s.starts_with("#")
+            s if s.starts_with('#')
                 && s.len() == 7
                 && s[1..].as_bytes().iter().all(|&b| {
-                    (b >= b'0' && b <= b'9') || (b >= b'a' && b <= b'f') || (b >= b'A' && b <= b'F')
+                    (b'0'..=b'9').contains(&b)
+                        || (b'a'..=b'f').contains(&b)
+                        || (b'A'..=b'F').contains(&b)
                 }) =>
             {
                 return Ok(Color::Rgb(
@@ -406,10 +408,12 @@ impl Color {
                         .map_err(|_| de::Error::custom("invalid `color` value"))?,
                 ))
             }
-            s if s.starts_with("#")
+            s if s.starts_with('#')
                 && s.len() == 4
                 && s[1..].as_bytes().iter().all(|&b| {
-                    (b >= b'0' && b <= b'9') || (b >= b'a' && b <= b'f') || (b >= b'A' && b <= b'F')
+                    (b'0'..=b'9').contains(&b)
+                        || (b'a'..=b'f').contains(&b)
+                        || (b'A'..=b'F').contains(&b)
                 }) =>
             {
                 return Ok(Color::Rgb(
@@ -421,7 +425,8 @@ impl Color {
                         .map_err(|_| de::Error::custom("invalid `color` value"))?,
                 ))
             }
-            _ => u8::from_str_radix(&s, 10)
+            _ => s
+                .parse::<u8>()
                 .map_err(|_| de::Error::custom("invalid `color` value"))?,
         };
         Ok(Color::Byte(byte))
diff --git a/src/terminal/embed/grid.rs b/src/terminal/embed/grid.rs
index 35837697..cd74e795 100644
--- a/src/terminal/embed/grid.rs
+++ b/src/terminal/embed/grid.rs
@@ -346,7 +346,7 @@ impl EmbedGrid {
                 *state = State::CsiQ(buf1);
             }
             /* OSC stuff */
-            (c, State::Osc1(ref mut buf)) if (c >= b'0' && c <= b'9') || c == b'?' => {
+            (c, State::Osc1(ref mut buf)) if (b'0'..=b'9').contains(&c) || c == b'?' => {
                 buf.push(c);
             }
             (b';', State::Osc1(ref mut buf1_p)) => {
@@ -354,7 +354,7 @@ impl EmbedGrid {
                 let buf2 = SmallVec::new();
                 *state = State::Osc2(buf1, buf2);
             }
-            (c, State::Osc2(_, ref mut buf)) if (c >= b'0' && c <= b'9') || c == b'?' => {
+            (c, State::Osc2(_, ref mut buf)) if (b'0'..=b'9').contains(&c) || c == b'?' => {
                 buf.push(c);
             }
             /* Normal */
@@ -512,7 +512,7 @@ impl EmbedGrid {
                 *state = State::Normal;
             }
             /* CSI ? stuff */
-            (c, State::CsiQ(ref mut buf)) if c >= b'0' && c <= b'9' => {
+            (c, State::CsiQ(ref mut buf)) if (b'0'..=b'9').contains(&c) => {
                 buf.push(c);
             }
             (b'h', State::CsiQ(ref buf)) => {
@@ -569,7 +569,7 @@ impl EmbedGrid {
                 *state = State::Normal;
             }
             /* END OF CSI ? stuff */
-            (c, State::Csi) if c >= b'0' && c <= b'9' => {
+            (c, State::Csi) if (b'0'..=b'9').contains(&c) => {
                 let mut buf1 = SmallVec::new();
                 buf1.push(c);
                 *state = State::Csi1(buf1);
@@ -973,17 +973,9 @@ impl EmbedGrid {
                         *bg_color = Color::Default;
                     }
                     b"1" => { /* bold */ }
-                    b"7" => {
-                        /* Inverse */
-                        let temp = *fg_color;
-                        *fg_color = *bg_color;
-                        *bg_color = temp;
-                    }
-                    b"27" => {
-                        /* Inverse off */
-                        let temp = *fg_color;
-                        *fg_color = *bg_color;
-                        *bg_color = temp;
+                    b"7" | b"27" => {
+                        /* Inverse on/off */
+                        std::mem::swap(&mut (*fg_color), &mut (*bg_color))
                     }
                     b"30" => *fg_color = Color::Black,
                     b"31" => *fg_color = Color::Red,
@@ -1037,17 +1029,9 @@ impl EmbedGrid {
                             *bg_color = Color::Default;
                         }
                         b"1" => { /* bold */ }
-                        b"7" => {
-                            /* Inverse */
-                            let temp = *fg_color;
-                            *fg_color = *bg_color;
-                            *bg_color = temp;
-                        }
-                        b"27" => {
-                            /* Inverse off */
-                            let temp = *fg_color;
-                            *fg_color = *bg_color;
-                            *bg_color = temp;
+                        b"7" | b"27" => {
+                            /* Inverse  on/off */
+                            std::mem::swap(&mut (*fg_color), &mut (*bg_color))
                         }
                         b"30" => *fg_color = Color::Black,
                         b"31" => *fg_color = Color::Red,
@@ -1094,7 +1078,7 @@ impl EmbedGrid {
                 grid[cursor_val!()].set_bg(*bg_color);
                 *state = State::Normal;
             }
-            (c, State::Csi1(ref mut buf)) if (c >= b'0' && c <= b'9') || c == b' ' => {
+            (c, State::Csi1(ref mut buf)) if (b'0'..=b'9').contains(&c) || c == b' ' => {
                 buf.push(c);
             }
             (b';', State::Csi2(ref mut buf1_p, ref mut buf2_p)) => {
@@ -1144,7 +1128,7 @@ impl EmbedGrid {
                 //debug!("cursor became: {:?}", cursor);
                 *state = State::Normal;
             }
-            (c, State::Csi2(_, ref mut buf)) if c >= b'0' && c <= b'9' => {
+            (c, State::Csi2(_, ref mut buf)) if (b'0'..=b'9').contains(&c) => {
                 buf.push(c);
             }
             (b'r', State::Csi2(_, _)) | (b'r', State::Csi) => {
@@ -1177,7 +1161,7 @@ impl EmbedGrid {
                 *state = State::Normal;
             }
 
-            (c, State::Csi3(_, _, ref mut buf)) if c >= b'0' && c <= b'9' => {
+            (c, State::Csi3(_, _, ref mut buf)) if (b'0'..=b'9').contains(&c) => {
                 buf.push(c);
             }
             (b'm', State::Csi3(ref buf1, ref buf2, ref buf3))
@@ -1185,7 +1169,7 @@ impl EmbedGrid {
             {
                 /* Set character attributes | foreground color */
                 *fg_color = if let Ok(byte) =
-                    u8::from_str_radix(unsafe { std::str::from_utf8_unchecked(buf3) }, 10)
+                    unsafe { std::str::from_utf8_unchecked(buf3) }.parse::<u8>()
                 {
                     //debug!("parsed buf as {}", byte);
                     Color::Byte(byte)
@@ -1200,7 +1184,7 @@ impl EmbedGrid {
             {
                 /* Set character attributes | background color */
                 *bg_color = if let Ok(byte) =
-                    u8::from_str_radix(unsafe { std::str::from_utf8_unchecked(buf3) }, 10)
+                    unsafe { std::str::from_utf8_unchecked(buf3) }.parse::<u8>()
                 {
                     //debug!("parsed buf as {}", byte);
                     Color::Byte(byte)
@@ -1246,3 +1230,9 @@ impl EmbedGrid {
         }
     }
 }
+
+impl Default for EmbedGrid {
+    fn default() -> Self {
+        Self::new()
+    }
+}
diff --git a/src/terminal/keys.rs b/src/terminal/keys.rs
index bdb4f456..bfc3ac2b 100644
--- a/src/terminal/keys.rs
+++ b/src/terminal/keys.rs
@@ -182,7 +182,7 @@ pub fn get_events(
         select! {
             default => {
                 if stdin_fd.revents().is_some() {
-                    'stdin_while: while let Some(c) = stdin_iter.next(){
+                    'stdin_while: for c in stdin_iter.by_ref() {
                         match (c, &mut input_mode) {
                             (Ok((TermionEvent::Key(k), bytes)), InputMode::Normal) => {
                                 closure((Key::from(k), bytes));
@@ -192,7 +192,7 @@ pub fn get_events(
                                 Ok((TermionEvent::Key(TermionKey::Char(k)), ref mut bytes)), InputMode::Paste(ref mut buf),
                             ) => {
                                 paste_buf.push(k);
-                                let bytes = std::mem::replace(bytes, Vec::new());
+                                let bytes = std::mem::take(bytes);
                                 buf.extend(bytes.into_iter());
                                 continue 'stdin_while;
                             }
@@ -203,7 +203,7 @@ pub fn get_events(
                             (Ok((TermionEvent::Unsupported(ref k), _)), InputMode::Paste(ref mut buf))
                                 if k.as_slice() == BRACKET_PASTE_END =>
                                 {
-                                    let buf = std::mem::replace(buf, Vec::new());
+                                    let buf = std::mem::take(buf);
                                     input_mode = InputMode::Normal;
                                     let ret = Key::from(&paste_buf);
                                     paste_buf.clear();
@@ -277,12 +277,12 @@ impl<'de> Deserialize<'de> for Key {
                     "Enter" | "enter" => Ok(Key::Char('\n')),
                     "Tab" | "tab" => Ok(Key::Char('\t')),
                     "Esc" | "esc" => Ok(Key::Esc),
-                    ref s if s.len() == 1 => Ok(Key::Char(s.chars().nth(0).unwrap())),
-                    ref s if s.starts_with("F") && (s.len() == 2 || s.len() == 3) => {
+                    s if s.len() == 1 => Ok(Key::Char(s.chars().next().unwrap())),
+                    s if s.starts_with('F') && (s.len() == 2 || s.len() == 3) => {
                         use std::str::FromStr;
 
                         if let Ok(n) = u8::from_str(&s[1..]) {
-                            if n >= 1 && n <= 12 {
+                            if (1..=12).contains(&n) {
                                 return Ok(Key::F(n));
                             }
                         }
@@ -291,7 +291,7 @@ impl<'de> Deserialize<'de> for Key {
                                     &s[1..]
                         )))
                     }
-                    ref s if s.starts_with("M-") && s.len() == 3 => {
+                    s if s.starts_with("M-") && s.len() == 3 => {
                         let c = s.as_bytes()[2] as char;
 
                         if c.is_lowercase() || c.is_numeric() {
@@ -303,7 +303,7 @@ impl<'de> Deserialize<'de> for Key {
                                     &s[2..]
                         )))
                     }
-                    ref s if s.starts_with("C-") && s.len() == 3 => {
+                    s if s.starts_with("C-") && s.len() == 3 => {
                         let c = s.as_bytes()[2] as char;
 
                         if c.is_lowercase() || c.is_numeric() {
diff --git a/src/types.rs b/src/types.rs
index eec5b51b..158d8281 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -149,12 +149,12 @@ pub enum UIEvent {
     GlobalUIDialog(Box<dyn Component>),
     Timer(Uuid),
     ConfigReload {
-        old_settings: crate::conf::Settings,
+        old_settings: Box<crate::conf::Settings>,
     },
     VisibilityChange(bool),
 }
 
-pub struct CallbackFn(pub Box<dyn FnOnce(&mut crate::Context) -> () + Send + 'static>);
+pub struct CallbackFn(pub Box<dyn FnOnce(&mut crate::Context) + Send + 'static>);
 
 impl core::fmt::Debug for CallbackFn {
     fn fmt(&self, fmt: &mut core::fmt::Formatter) -> core::fmt::Result {
@@ -322,8 +322,6 @@ pub struct RateLimit {
     last_tick: std::time::Instant,
     pub timer: crate::jobs::Timer,
     rate: std::time::Duration,
-    reqs: u64,
-    millis: std::time::Duration,
     pub active: bool,
 }
 
@@ -336,8 +334,6 @@ impl RateLimit {
                 std::time::Duration::from_millis(millis),
             ),
             rate: std::time::Duration::from_millis(millis / reqs),
-            reqs,
-            millis: std::time::Duration::from_millis(millis),
             active: false,
         }
     }
diff --git a/src/types/helpers.rs b/src/types/helpers.rs
index 87850e49..1f33f676 100644
--- a/src/types/helpers.rs
+++ b/src/types/helpers.rs
@@ -36,7 +36,7 @@ pub struct File {
 impl Drop for File {
     fn drop(&mut self) {
         if self.delete_on_drop {
-            std::fs::remove_file(self.path()).unwrap_or_else(|_| {});
+            let _ = std::fs::remove_file(self.path());
         }
     }
 }
@@ -54,6 +54,7 @@ impl File {
     pub fn path(&self) -> &PathBuf {
         &self.path
     }
+
     pub fn read_to_string(&self) -> String {
         let mut buf = Vec::new();
         let mut f = fs::File::open(&self.path)