diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index c60aa0f09be..b44f5c9f954 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -294,6 +294,9 @@ pub struct GlobalScope {
     ///
     /// <https://html.spec.whatwg.org/multipage/#about-to-be-notified-rejected-promises-list>
     #[ignore_malloc_size_of = "mozjs"]
+    // `Heap` values must stay boxed, as they need semantics like `Pin`
+    // (that is, they cannot be moved).
+    #[allow(clippy::vec_box)]
     uncaught_rejections: DomRefCell<Vec<Box<Heap<*mut JSObject>>>>,
 
     /// Promises in this list have previously been reported as rejected
@@ -302,6 +305,9 @@ pub struct GlobalScope {
     ///
     /// <https://html.spec.whatwg.org/multipage/#outstanding-rejected-promises-weak-set>
     #[ignore_malloc_size_of = "mozjs"]
+    // `Heap` values must stay boxed, as they need semantics like `Pin`
+    // (that is, they cannot be moved).
+    #[allow(clippy::vec_box)]
     consumed_rejections: DomRefCell<Vec<Box<Heap<*mut JSObject>>>>,
 
     /// True if headless mode.
@@ -2194,6 +2200,9 @@ impl GlobalScope {
         }
     }
 
+    // `Heap` values must stay boxed, as they need semantics like `Pin`
+    // (that is, they cannot be moved).
+    #[allow(clippy::vec_box)]
     pub fn get_uncaught_rejections(&self) -> &DomRefCell<Vec<Box<Heap<*mut JSObject>>>> {
         &self.uncaught_rejections
     }
@@ -2215,6 +2224,9 @@ impl GlobalScope {
         }
     }
 
+    // `Heap` values must stay boxed, as they need semantics like `Pin`
+    // (that is, they cannot be moved).
+    #[allow(clippy::vec_box)]
     pub fn get_consumed_rejections(&self) -> &DomRefCell<Vec<Box<Heap<*mut JSObject>>>> {
         &self.consumed_rejections
     }