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### Which website or app were you using when the bug happened?

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### What were you doing on the website or app when the bug happened?

If possible, please describe how to reproduce this bug on the website or app mentioned above:
1. <!-- FILL THIS IN -->
2. <!-- FILL THIS IN -->
3. <!-- FILL THIS IN -->

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### Generated information

DevTools version: 4.13.1-93782cfed2

Call stack:
(none)

Component stack:
(none)

GitHub URL search query:
https://api.github.com/search/issues?q=Cannot%20add%20node%20%20because%20a%20node%20with%20that%20id%20is%20already%20in%20the%20Store.%20in%3Atitle%20is%3Aissue%20is%3Aopen%20is%3Apublic%20label%3A%22Component%3A%20Developer%20Tools%22%20repo%3Afacebook%2Freact
The
       chi
       to 
      for (let j = 0; j < pendingSimulatedUnmountedIDs.length; j++) {
        operations[i + j] = pendingSimulatedUnmountedIDs[j];
      }
      i += pendingSimulatedUnmountedIDs.length;
       The 
      if (pendingUnmountedRootID !== null) {
        operations[i] = pendingUnmountedRootID;
        i++;
      }
    }
     Fill in the rest of the operations.
    for (let j = 0; j < pendingOperations.length; j++) {
      operations[i + j] = pendingOperations[j];
    }
    i += pendingOperations.length;
     Let the frontend know about tree operations.
    flushOrQueueOperations(operations);
     Reset all of the pending state now that we've told the frontend about it.
    pendingOperations.length = 0;
    pendingRealUnmountedIDs.length = 0;
    pendingSimulatedUnmountedIDs.length = 0;
    pendingUnmountedRootID = null;
    pendingStringTable.clear();
    pendingStringTableLength = 0;
  }
  function getStringID(str: string | null): number {
    if (str === null) {