## 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
isFirstMount: boolean,
  props: Array<string> | null,
  state: Array<string> | null,
|};
export type CommitDataBackend = {|
  
  changeDescriptions: Array<[number, ChangeDescription]> | null,
  duration: number,
  
  fiberActualDurations: Array<[number, number]>,
  
  fiberSelfDurations: Array<[number, number]>,
  interactionIDs: Array<number>,
  priorityLevel: string | null,
  timestamp: number,
|};
export type ProfilingDataForRootBackend = {|
  commitData: Array<CommitDataBackend>,
  displayName: string,
  
  initialTreeBaseDurations: Array<[number, number]>,
  
  interactionCommits: Array<[number, Array<number>]>,
  interactions: Array<[number, Interaction]>,
  rootID: number,
|};
export type ProfilingDataBackend = {|
  dataForRoots: Array<ProfilingDataForRootBackend>,
  rendererID: number,
|};