Childframe remains after losing focus

[flatwhatson]

Childframes remain "on top" after Emacs loses focus, or changing virtual desktop.

Before changing focus:

After changing focus:

After changing desktop:

I'm running the X11 backend on Plasma.

[fejfighter]

I think I will need to investigate how gnome builder does it's completion popups, I know emacs is weird, but I'm already setting every association in gtkwindow*

this is confirmed as is #49

[fejfighter]

in spite of what I said on #49 I think this still applies for wayland, though it;s not as dramatic, "clicking out" of a completion with company-posframe does not drop the child frame and that should.

[masm11]

fixed by #51.