## 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
import type {ResolveNativeStyle} from 'react-devtools-shared/src/backend/NativeStyleEditor/setupNativeStyleEditor';
type BundleType =
  | 0 
  | 1; 
export type WorkTag = number;
export type SideEffectTag = number;
export type ExpirationTime = number;
export type WorkTagMap = {|
  Block: WorkTag,
  ClassComponent: WorkTag,
  ContextConsumer: WorkTag,
  ContextProvider: WorkTag,
  CoroutineComponent: WorkTag,
  CoroutineHandlerPhase: WorkTag,
  DehydratedSuspenseComponent: WorkTag,
  ForwardRef: WorkTag,
  Fragment: WorkTag,
  FunctionComponent: WorkTag,
  HostComponent: WorkTag,
  HostPortal: WorkTag,
  HostRoot: WorkTag,
  HostText: WorkTag,
  IncompleteClassComponent: WorkTag,
  IndeterminateComponent: WorkTag,
  LazyComponent: WorkTag,
  MemoComponent: WorkTag,
  Mode: WorkTag,
  Profiler: WorkTag,
  SimpleMemoComponent: WorkTag,
  SuspenseComponent: WorkTag,