Override redirect windows with keyboard grabs on Xwayland

[Olivier Fourdan]

Hi all,

First of all, sorry for cross posting, but I am not really sure where the issue is to be addressed...

I am looking into https://bugs.freedesktop.org/show_bug.cgi?id=96547 and concluded this is actually the same as  https://bugzilla.gnome.org/show_bug.cgi?id=752956

Basically, long story short, we have clients in X that map a full-screen override redirect window with a keyboard/mouse active grab for the user to enter a password.

Because override redirect windows are not managed by X11 window managers, these won't focus the O-R window by themselves but that's not a problem on X11 thanks to the active grab.

Things get more complicated with those clients on Xwayland, because the X11 active grab cannot be honoured in Wayland, and therefore the window may or may not get focused automatically, depending on the compositor/WM. In the worst case, the user might type his/her password in some other (focused but hidden underneath) window without even knowing it!

I am not sure how or even where to address such cases... Suggestions welcome.

PS: weston and gnome-shell differ here, weston will give focus to the O-R window but will obviously allow for alt-tab and can sometimes segfault afterwards - that's a bug in weston, but off topic for now - gnome-shell will *not* focus the O-R window and seems right in doing to, but that obviously breaks those apps that map an O-R window with a grab on the keyboard.

Cheers,
Olivier