SUMMARY as soon as the first (topmost) keyboard layout has the acute key (`) configured as "dead" (e.g. US-intl, with dead keys, or German with acute dead), this task switcher function stops working. STEPS TO REPRODUCE 1. ubuntu 20.04 with kubuntu-desktop packages installed. 2. set first keyboard layout to a layout with acute dead (e.g. US-intl, with dead keys) OBSERVED RESULT Alt+` (switch between windows of same application) stops working EXPECTED RESULT Alt+` should continue working (e.g. like with a non-dead key keyboard) SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: ubuntu 20.04 64b (available in About System) KDE Plasma Version: 5.18.5 KDE Frameworks Version: 5.68.0 Qt Version: 5.12.8 ADDITIONAL INFORMATION I think this is KDE specific, same installation on same computer, switching to Gnome, and no problem. Over time, I also used different DE/distributions on different computers, and I only have this problem when coming back to KDE.
*** This bug has been marked as a duplicate of bug 336750 ***