In this [issue](https://github.com/facebook/react/issues/23373), when you navigate to [this app](https://next-rsc-notes.vercel.app/note/1646289027680) and inspect the sidebar in the components tab, you will get this error:

![image](https://user-images.githubusercontent.com/2735514/158241727-64eba8f9-5ac2-4aa7-bffa-ff9b3174a261.png)

 This is a user error. One of the components in the user's app thrown. However, the UI for this is confusing, because it seems like it's a DevTools error. We've gotten a lot of bug reports like this, and it would be good to differentiate between DevTools bugs and bugs in the app. For this task:

- [ ] Build the React DevTools extension locally (instructions [here](https://github.com/facebook/react/tree/main/packages/react-devtools-extensions)) and reproduce the error
- [ ] Figure out a way to have the front end be able to differentiate whether the error is a error within DevTools or within the user's app
- [ ] Design/implement a better UI to help app developers distinguish between these two cases
});
    recordPendingErrorsAndWarnings();
  }
  function mergeMapsAndGetCountHelper(
    fiber: Fiber,
    fiberID: number,
    pendingFiberToMessageCountMap: Map<Fiber, Map<string, number>>,
    fiberIDToMessageCountMap: Map<number, Map<string, number>>,
  ): number {
    let newCount = 0;
    let messageCountMap = fiberIDToMessageCountMap.get(fiberID);
    const pendingMessageCountMap = pendingFiberToMessageCountMap.get(fiber);
    if (pendingMessageCountMap != null) {
      if (messageCountMap == null) {
        messageCountMap = pendingMessageCountMap;
        fiberIDToMessageCountMap.set(fiberID, pendingMessageCountMap);
      } else {
         T
        const refinedMessageCountMap = ((messageCountMap: any): Map<
          string,
          number,
        >);
        pendingMessageCountMap.forEach((pendingCount, message) => {
          const previousCount = refinedMessageCountMap.get(message) || 0;
          refinedMessageCountMap.set(message, previousCount + pendingCount);
        });
      }
    }
    if (!shouldFilterFiber(fiber)) {
      if (messageCountMap != null) {