1) open thunderbird
2) don't give it focus (don't click in the window), but minimize it
3) open firefox
4) bring thunderbird back using message indicator
==> firefox window stays on top of the display, but thunderbird has focus. Clicks happen in thunderbird.
Another way to trigger the (supposedly same) bug:
1) open thunderbird
2) don't give it focus (don't click in the window), but minimize it
3) open firefox
4) bring thunderbird back using message indicator
==> firefox window stays on top of the display, but thunderbird has focus. Clicks happen in thunderbird.