[UX issue] fullscreen window + modal windows: do not behave as expected, and difficult to recover from

[inga-lovinde]

For example:

• Open Firefox; open any page in it;
• Enter fullscreen mode with F11;
• Right-click, "save page as" (the same applies to "save link as", "save image as", etc; the same applies to chromium).

Expected result: floating file picker appears on top of a full-screen firefox view. Actual result: nothing appears on the screen (presumably file picker is displayed behind firefox view), firefox no longer reacts to any key presses or clicks (presumably because the focus is on the file picker), F11 does not work too (presumably because the focus is on the file picker).

The same behavior applies to the other apps with full-screen views as well (e.g. Telegram Desktop always opens images on full screen, and trying to "save as" from there also leads to invisible but focused file picker).

Sometimes I can recover from this by repeatedly pressing Esc, apparently one of these key presses exits the invisible file picker and returns the focus to full-screen view.

Sometimes the only way to recover from this seems to be to hide the tag full-screen view belongs to (e.g. by Super+Number switching to another "desktop"), and killing the process of that view from the terminal.

I'm not sure if this is a bug or not, but this is certainly an UX issue; at least there should be a way to gracefully recover from this? And the best solution I think would be to display floating views on top of full-screen ones, not behind them.