Popover2 tabindex

[dlech]

Environment

• Package version(s): "@blueprintjs/popover2": "^0.1.1",
• Operating System: Ubuntu 20.04
• Browser name and version: Chromium Version 88.0.4324.96 (Official Build) snap (64-bit)

Code Sandbox

Link to a minimal repro (fork this code sandbox): https://codesandbox.io/s/blueprint-sandbox-forked-146cf?file=/src/CoreExample.tsx

The example has been modified to add Tooltip2 around the Core Sandbox buttons.

Steps to reproduce

1. click on a blank part of the browser
2. press tab on the keyboard to focus the buttons
3. notice that each button is focused twice

Actual behavior

Each button is focused twice, once for the button element and once for the tooltip element.

Expected behavior

The buttons should only be focused once.

Possible solution

Don't apply tabindex to the tooltip element if child already has tabindex or make it configurable.

[adidahiya]

Thanks for taking the new package for a spin. Good catch, I'll fix this ASAP.

[adidahiya]

Fix open in PR #4512