Focusing on React Select

### Are you submitting a **bug report** or a **feature request**?
Request

### What is the current behavior?
Focus does not appear to work out of the box with React Select.

### What is the expected behavior?
Seeing as React Select is so popular and people tend to use it with React Final Form so much, could we get this to work out of the box?

Alternatively if there is a simple or well known solution, would anyone mind sharing it here?
### Sandbox Link
No link. Using the Third Party link in the examples can show the issue.

### What's your environment?
Mac OS 10.15. FireFox or Chrome. Everything latest at the time of this post, but as this is a feature request, I don’t think this pertains?

### Other information

Start with the Third Party example mentioned in the issue and reproduce the focus behavior with React Select. Determine what “out of the box” support should mean and confirm the expected behavior before changing anything; the issue does not name implementation files or tests.

Written by the indexing model from the issue text.