How to install React Dev Tools v3 so that you can have highlight updates again

install react-devtools v3

1. Somewhere on your machine clone the project.
```
> git clone https://github.com/facebook/react-devtools.git
> cd react-devtools
```

2. Switch to the v3 branch
```
> git checkout v3
```

3. Install all dependencies.
```
> yarn
```

4. Package up the Chrome extension.
```
> yarn build:extension
```

5. In Chrome, go to `chrome://extensions`. Enable developer mode (top right).

6. Click 'Load unpacked' (top left) and select to `react-devtools/shells/chrome/build/unpacked`.

7. If you have the official dev tools extension installed, disable it.