diff --git a/pkgs/collection/CHANGELOG.md b/pkgs/collection/CHANGELOG.md
index 2891b0dc..32318658 100644
--- a/pkgs/collection/CHANGELOG.md
+++ b/pkgs/collection/CHANGELOG.md
@@ -4,6 +4,7 @@
   `Map.entries`.
 - Optimize equality and hash code for maps by using `update` and a `values`
   iterator to avoid extra lookups.
+- Address diagnostics from `strict_top_level_inference`.
 
 ## 1.19.1
 
diff --git a/pkgs/collection/README.md b/pkgs/collection/README.md
index 63f705c7..8c72c67e 100644
--- a/pkgs/collection/README.md
+++ b/pkgs/collection/README.md
@@ -56,4 +56,4 @@ functions on an existing object.
 
 Please file feature requests and bugs at the [issue tracker][tracker].
 
-[tracker]: https://github.com/dart-lang/collection/issues
+[tracker]: https://github.com/dart-lang/core/issues/new/choose
diff --git a/pkgs/collection/lib/src/unmodifiable_wrappers.dart b/pkgs/collection/lib/src/unmodifiable_wrappers.dart
index 3b211c07..a73a55b3 100644
--- a/pkgs/collection/lib/src/unmodifiable_wrappers.dart
+++ b/pkgs/collection/lib/src/unmodifiable_wrappers.dart
@@ -194,11 +194,13 @@ abstract mixin class UnmodifiableMapMixin<K, V> implements Map<K, V> {
   @override
   void clear() => _throw();
 
-  /// Throws an [UnsupportedError];
-  /// operations that change the map are disallowed.
-  set first(_) => _throw();
-
-  /// Throws an [UnsupportedError];
-  /// operations that change the map are disallowed.
-  set last(_) => _throw();
+  /// Throws an [UnsupportedError].
+  // ignore: provide_deprecation_message
+  @deprecated
+  set first(Object? _) => _throw();
+
+  /// Throws an [UnsupportedError].
+  // ignore: provide_deprecation_message
+  @deprecated
+  set last(Object? _) => _throw();
 }
diff --git a/pkgs/collection/test/extensions_test.dart b/pkgs/collection/test/extensions_test.dart
index 6c5b45f1..dd920597 100644
--- a/pkgs/collection/test/extensions_test.dart
+++ b/pkgs/collection/test/extensions_test.dart
@@ -2225,7 +2225,7 @@ Iterable<T> iterable<T>(Iterable<T> values) sync* {
   yield* values;
 }
 
-Never unreachable([_, __, ___]) => fail('Unreachable');
+Never unreachable([dynamic _, dynamic __, dynamic ___]) => fail('Unreachable');
 
 String toString(Object? o) => '$o';