## 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
CONCURRENT_MODE_SYMBOL_STRING,
  DEPRECATED_ASYNC_MODE_SYMBOL_STRING,
  PROVIDER_NUMBER,
  PROVIDER_SYMBOL_STRING,
  CONTEXT_NUMBER,
  CONTEXT_SYMBOL_STRING,
  STRICT_MODE_NUMBER,
  STRICT_MODE_SYMBOL_STRING,
  PROFILER_NUMBER,
  PROFILER_SYMBOL_STRING,
  SCOPE_NUMBER,
  SCOPE_SYMBOL_STRING,
  FORWARD_REF_NUMBER,
  FORWARD_REF_SYMBOL_STRING,
  MEMO_NUMBER,
  MEMO_SYMBOL_STRING,
} from './ReactSymbols';
import type {Fiber} from 'react-reconciler/src/ReactInternalTypes';
import type {
  ChangeDescription,
  CommitDataBackend,
  DevToolsHook,
  InspectedElement,
  InspectedElementPayload,
  InstanceAndStyle,
  NativeType,
  Owner,
  PathFrame,
  PathMatch,
  ProfilingDataBackend,