diff --git a/src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/ComWrappers.cs b/src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/ComWrappers.cs
index aff669dd7acacc..551f84fc1ec3e5 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/ComWrappers.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Runtime/InteropServices/ComWrappers.cs
@@ -669,7 +669,7 @@ internal sealed class ReferenceTrackerNativeObjectWrapper : NativeObjectWrapper
             internal readonly IntPtr _contextToken;
             private int _trackerObjectDisconnected; // Atomic boolean, so using int.
             private readonly bool _releaseTrackerObject;
-            internal readonly GCHandle _nativeObjectWrapperWeakHandle;
+            internal GCHandle _nativeObjectWrapperWeakHandle; // mutable struct; do not make this readonly
 
             public IntPtr TrackerObject => (_trackerObject == IntPtr.Zero || _trackerObjectDisconnected == 1) ? IntPtr.Zero : _trackerObject;