- Pressing Command+Q to quit Gretl brings up the "save
commands" dialog with the Yes button highlighted. Navigating
to the No button doesn't highlight the No button but only
show a highlighted border. Navigating to the other buttons
in that dialog does highlight the complete button.

Hmm, I can arrow-key to "No" successfully here.

I can arrow key too but the No button itself is not highlighted but only the border around the button (very thinly).

See the attachment.