diff --git a/components/script/dom/baseaudiocontext.rs b/components/script/dom/baseaudiocontext.rs
index cfbc2516925..d0cfc8ab203 100644
--- a/components/script/dom/baseaudiocontext.rs
+++ b/components/script/dom/baseaudiocontext.rs
@@ -5,7 +5,6 @@
 use std::cell::Cell;
 use std::collections::hash_map::Entry;
 use std::collections::{HashMap, VecDeque};
-use std::mem;
 use std::rc::Rc;
 use std::sync::{Arc, Mutex};
 
diff --git a/components/script/dom/bindings/refcounted.rs b/components/script/dom/bindings/refcounted.rs
index 3e856b63d0f..784e71ff3aa 100644
--- a/components/script/dom/bindings/refcounted.rs
+++ b/components/script/dom/bindings/refcounted.rs
@@ -247,7 +247,7 @@ impl LiveDOMReferences {
     #[allow(crown::unrooted_must_root)]
     fn addref_promise(&self, promise: Rc<Promise>) {
         let mut table = self.promise_table.borrow_mut();
-        table.entry(&*promise).or_insert(vec![]).push(promise)
+        table.entry(&*promise).or_default().push(promise)
     }
 
     /// ptr must be a pointer to a type that implements DOMObject.
@@ -297,7 +297,7 @@ fn remove_nulls<K: Eq + Hash + Clone, V>(table: &mut HashMap<K, Weak<V>>) {
 #[allow(crown::unrooted_must_root)]
 pub unsafe fn trace_refcounted_objects(tracer: *mut JSTracer) {
     info!("tracing live refcounted references");
-    LIVE_REFERENCES.with(|ref r| {
+    LIVE_REFERENCES.with(|r| {
         let r = r.borrow();
         let live_references = r.as_ref().unwrap();
         {
diff --git a/components/script/dom/bindings/root.rs b/components/script/dom/bindings/root.rs
index 088f93d12e0..906816f4812 100644
--- a/components/script/dom/bindings/root.rs
+++ b/components/script/dom/bindings/root.rs
@@ -64,7 +64,7 @@ where
     pub unsafe fn new(value: T) -> Self {
         unsafe fn add_to_root_list(object: *const dyn JSTraceable) -> *const RootCollection {
             assert_in_script();
-            STACK_ROOTS.with(|ref root_list| {
+            STACK_ROOTS.with(|root_list| {
                 let root_list = &*root_list.get().unwrap();
                 root_list.root(object);
                 root_list
@@ -208,7 +208,7 @@ where
     T: DomObject,
 {
     fn clone(&self) -> DomRoot<T> {
-        DomRoot::from_ref(&*self)
+        DomRoot::from_ref(self)
     }
 }
 
@@ -244,7 +244,7 @@ impl<'a> ThreadLocalStackRoots<'a> {
 
 impl<'a> Drop for ThreadLocalStackRoots<'a> {
     fn drop(&mut self) {
-        STACK_ROOTS.with(|ref r| r.set(None));
+        STACK_ROOTS.with(|r| r.set(None));
     }
 }
 
@@ -282,7 +282,7 @@ impl RootCollection {
 /// SM Callback that traces the rooted reflectors
 pub unsafe fn trace_roots(tracer: *mut JSTracer) {
     debug!("tracing stack roots");
-    STACK_ROOTS.with(|ref collection| {
+    STACK_ROOTS.with(|collection| {
         let collection = &*(*collection.get().unwrap()).roots.get();
         for root in collection {
             (**root).trace(tracer);
diff --git a/components/script/dom/bindings/str.rs b/components/script/dom/bindings/str.rs
index c7568f2c351..070c674d596 100644
--- a/components/script/dom/bindings/str.rs
+++ b/components/script/dom/bindings/str.rs
@@ -275,7 +275,7 @@ impl DOMString {
                     '2' => State::HourLow03,
                     _ => State::Error,
                 },
-                State::HourLow09 => next_state(c.is_digit(10), State::MinuteColon),
+                State::HourLow09 => next_state(c.is_ascii_digit(), State::MinuteColon),
                 State::HourLow03 => next_state(c.is_digit(4), State::MinuteColon),
 
                 // Step 2 ":"
@@ -283,20 +283,20 @@ impl DOMString {
 
                 // Step 3 "mm"
                 State::MinuteHigh => next_state(c.is_digit(6), State::MinuteLow),
-                State::MinuteLow => next_state(c.is_digit(10), State::SecondColon),
+                State::MinuteLow => next_state(c.is_ascii_digit(), State::SecondColon),
 
                 // Step 4.1 ":"
                 State::SecondColon => next_state(c == ':', State::SecondHigh),
                 // Step 4.2 "ss"
                 State::SecondHigh => next_state(c.is_digit(6), State::SecondLow),
-                State::SecondLow => next_state(c.is_digit(10), State::MilliStop),
+                State::SecondLow => next_state(c.is_ascii_digit(), State::MilliStop),
 
                 // Step 4.3.1 "."
                 State::MilliStop => next_state(c == '.', State::MilliHigh),
                 // Step 4.3.2 "SSS"
-                State::MilliHigh => next_state(c.is_digit(10), State::MilliMiddle),
-                State::MilliMiddle => next_state(c.is_digit(10), State::MilliLow),
-                State::MilliLow => next_state(c.is_digit(10), State::Done),
+                State::MilliHigh => next_state(c.is_ascii_digit(), State::MilliMiddle),
+                State::MilliMiddle => next_state(c.is_ascii_digit(), State::MilliLow),
+                State::MilliLow => next_state(c.is_ascii_digit(), State::Done),
 
                 _ => State::Error,
             }