## 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
return 0;
    }
    const existingID = pendingStringTable.get(str);
    if (existingID !== undefined) {
      return existingID;
    }
    const stringID = pendingStringTable.size + 1;
    pendingStringTable.set(str, stringID);
    
    
    
    pendingStringTableLength += str.length + 1;
    return stringID;
  }
  let currentlyInspectedElementID: number | null = null;
  let currentlyInspectedPaths: Object = {};
  
  
  function mergeInspectedPaths(path: Array<string | number>) {
    let current = currentlyInspectedPaths;
    path.forEach(key => {
      if (!current[key]) {