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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?

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1. <!-- 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
Ide
     This enables roots to be mapped to renderers,
     Which in turn enables fiber props, states, and hooks to be inspected.
    let i = 0;
    operations[i++] = rendererID;
    operations[i++] = currentRootID;
     Now fill in the string table.
     [stringTableLength, str1Length, ...str1, str2Length, ...str2, ...]
    operations[i++] = pendingStringTableLength;
    pendingStringTable.forEach((value, key) => {
      operations[i++] = key.length;
      const encodedKey = utfEncodeString(key);
      for (let j = 0; j < encodedKey.length; j++) {
        operations[i + j] = encodedKey[j];
      }
      i += key.length;
    });
    if (numUnmountIDs > 0) {
       All 
      operations[i++] = TREE_OPERATION_REMOVE;
       The 
      operations[i++] = numUnmountIDs;
       Fil
       The
       So 
      for (let j = pendingRealUnmountedIDs.length - 1; j >= 0; j--) {
        operations[i++] = pendingRealUnmountedIDs[j];
      }
       Fil
       (We