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Author: kassens

packages/react-reconciler/src/ReactFiberClassComponent.js

@@ -821,6 +821,9 @@ function mountClassInstance(
   instance.props = newProps;
   instance.state = workInProgress.memoizedState;
   if (!disableStringRefs) {
+    // When string refs are used in create-react-class legacy components,
+    // we need to make refs writable unless we patch all such copies of the
+    // class code that sets to a frozen emptyObject.
     instance.refs = {};
   }