Steps to replicate the issue (include links if applicable):
- Click on a MenuButton to open its menu
- Use the arrow keys to highlight one of the items
- Press Enter
What happens?: the menu closes, but the item that was highlighted is not selected
What should have happened instead?: the menu should close, and the item that was highlighted should be selected.
Prior to https://gerrit.wikimedia.org/r/c/design/codex/+/1169798, the selection behavior did work, but the menu would close and then immediately reopen, because of an interaction between the Menu's handling of the Enter key and the ToggleButton's handling of the Enter key. We chose to fix the menu not closing by temporarily breaking the selection behavior, but we should really fix both.
We might be able to do this by changing the ToggleButton to a regular Button (although that would change the design in other ways), or by somehow preventing the ToggleButton from reopening the menu after the Menu has already closed itself.