- Start typing a post
- Bring up a pop-up dialog via a toolbar button (e.g. "Hyperlink")
- Type/copypaste whatever you want and dismiss it with
<Enter>
- => In the textarea contol, Up and Down arrow keys now stop working
- -> If I dismiss the dialog by pressing a button in it with mouse, this doesn't happen
A workaround is to <Shift>-<Tab>
out of the control and <Tab>
back.
Firefox 59.0.2 x64 win7.