Describe what you were doing when the bug occurred:
1. I was using the devtools to investigate some performance issues w/ an app I help maintain
2. I had just turned on the "Record why each component rendered while profiling" checkbox
3. I ran a profile while navigating on the underlying page

The react profiler tab in the devtools gave this error, I think as I clicked the record icon to stop recording the profile.

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DevTools version: 4.5.0-355970aa4

Call stack: at N (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:160881)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:160015)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)
    at j (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:40:159939)

Component stack: in ec
    in div
    in div
    in div
    in So
    in Unknown
    in n
    in Unknown
    in div
    in div
    in rl
    in Ze
    in fn
    in Ga
    in _s
}
       I
       a
       p
      if (parentA.child === parentB.child) {
        let child = parentA.child;
        while (child) {
          if (child === a) {
             W
            if (isFiberMountedImpl(parentA) !== MOUNTED) {
              throw Error('Unable to find node on an unmounted component.');
            }
            return fiber;
          }
          if (child === b) {
             W
            if (isFiberMountedImpl(parentA) !== MOUNTED) {
              throw Error('Unable to find node on an unmounted component.');
            }
            return alternate;
          }
          child = child.sibling;
        }
         W
         w
        throw Error('Unable to find node on an unmounted component.');
      }
      if (a.return !== b.return) {
         T
         f