## The current behavior

The full value of the `key` is very difficult / impossible to find and use in the interface of the React Devtools.

![Kapture 2020-04-22 at 11 47 47](https://user-images.githubusercontent.com/1935696/79997715-25222680-84ba-11ea-97ba-51f1679a8c91.gif)

Only managed to find it by accident :(

## The expected behavior

The `key` is visible in the props list to the right.

### Detailed Proposal

As mentioned below in https://github.com/facebook/react/issues/18702#issuecomment-617924196

Add a light divider and new section in the props panel to the right.

Potentially also add a question mark that shows an explanation about the fact that things in this section are not really props.

Ref (Original implementation): https://github.com/facebook/react-devtools/pull/328
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          mightBeOnTrackedPath = false;
        } else {
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          mightBeOnTrackedPath = true;
        }
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        return false;
      }
    }
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    mightBeOnTrackedPath = false;
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    return true;
  }
  function updateTrackedPathStateAfterMount(mightSiblingsBeOnTrackedPath) {
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    mightBeOnTrackedPath = mightSiblingsBeOnTrackedPath;
  }
   Roots don't have a real persistent identity.
   A root's "pseudo key" is "childDisplayName:indexWithThatName".
   For example, "App:0" or, in case of similar roots, "Story:0", "Story:1", etc.
   We will use this to try to disambiguate roots when restoring selection between reloads.
  const rootPseudoKeys: Map<number, string> = new Map();
  const rootDisplayNameCounter: Map<string, number> = new Map();
  function setRootPseudoKey(id: number, fiber: Fiber) {