Running an older app that uses X Toolkit Intrinsics and Motif to create a full screen window. It uses XIM to handle input methods. When using e.g. Korean/Hangul input, the candidate panel does not always appear near the cursor as expected.
The problem has been reported as starting with CentOS 8 - same app works fine with the same input method on CentOS 6 & 7. I’m trying to troubleshoot it on CentOS 8.4 / gnome-shell v 3.32.2. This is all using Xorg/X11 (rather than wayland).
If a gnome terminal window is pinned above (‘Always on Top’), it does work as expected. I also find that it works fine after restarting the gnome-shell (gnome-shell -r), but stops working after using alt-tab to switch between applications.
I’ve examined the code path used in ui/ibusCandidatePopup.js for both the working (gnome-terminal pinned above) and non-working case, and it seems to be the same.
I also tried running gnome-shell using MUTTER_VERBOSE and examined the window stack in both the working and non-working case but couldn’t spot anything unexpected.
Any input on how to best troubleshoot this?