2020-10-19
Operating System: openSUSE Tumbleweed 20201014
KDE Plasma Version: 5.20.0
KDE Frameworks Version: 5.75.0
Qt Version: 5.15.1
Kernel Version: 5.8.14-1-default
Graphics Processor: llvmpipe
Running:
virtualbox-guest-x11 - VirtualBox X11 drivers for mouse and video 6.1.14-2.1
virtualbox-guest-tools - VirtualBox guest tools 6.1.14-2.1
virtualbox-guest-source - Source files for virtualbox guest kernel modules 6.1.14-2.1


Fault Summary:
The system settings keyboard shortcuts crashed.
No reaction in the Kde gui when typing keyboard shortcuts.
Eg. KWin: "Switch to Next Desktop", "Switch to Previous Desktop";
Eg. Plasma: "Switch to Next Activity", "Switch to Previous Activity";
The fault is caused by configuring in system settings a keyboard shortcut for an additional keyboard layout.


Error Symptoms:
Configure keyboard shortcuts in system settings.
Like:
System Settings > Workspace > Shortcuts:
System Services > KWin > Walk Through Windows: Default shortcut: Alt+Tab

Additional fault:
System Services > KWin > Walk Through Windows (Reverse): Default shortcut: Alt+Shift+Backtab
The above setting should display "Alt-Shift-Tab", not Alt+Shift+Backtab.

System Services > KWin > Walk Through Windows (Reverse): Custom shortcut: Alt+Shift+Tab
System Services > KWin > Switch to Next Desktop > Custom shortcut: Ctrl+Tab
System Services > KWin > Switch to Previous Desktop > Custom shortcut: Ctrl+Shift+Tab

Additional sporadic fault:
System Services > Plasma > Walk through activities > Custom: Meta+Tab
The above setting is displayed as "Meta+Tab, Tab, Tab"

Additional sporadic fault:
System Services > Plasma > Walk through activities > Custom: Meta+Shift+Tab
The above setting is displayed as "Meta+Shift+Tab, Backtab, Backtab"

System Services > Plasma > Walk through activities > Default shortcut: Meta+Tab
System Services > Plasma > Walk through activities (Reverse) > Default shortcut: Meta+Shift+Tab

Additional fault:
Keyboard > Shortcuts for Switching Layout > Alternative shortcut: Ctrl+Alt+K
Only this shortcut is displayed via the Kde plasma on-screen feedback (in the middle of the screen).

Eg. Configure keyboard options > Switching to another layout > "Left Alt+Left Shift".

The typed key-combination appears to be sent directly to the active kde foreground window, instead of being acted upon by the kde system settings for keyboard shortcuts.


Fault Reproduction:
Configure in System Settings an additional keyboard layout and assign a keyboard shortcut.
Like:
System Settings > Hardware > Input Devices:
Keyboard > Hardware > Keyboard model: Apple | Apple Aluminium (ANSI)
Keyboard > Layouts > Add: Layout: German, Default, Label de
Keyboard > Shortcuts for Switching Layout > Main shortcuts: "Left Alt+Left Shift"
Type a configured key combination, eg. for "Switch to Next Activity".


Fault Mitigation:
Reset to Defaults in "Kde > System Settings > Hardware > Input Devices > Keyboard > Advanced > Configure keyboard options > Switching to another layout > (Left Alt+Left Shift)".

Magically, all Kde keyboard shortcuts appear to function correctly; until the next reboot.
After reboot, if the fault is present again, configure the shortcut for switching between layouts again for "Left Alt+Left Shift".
Like:
Right-click on the Kde Panel Task Manager keyboard layout indicator (us) > Keyboard System Settings Module > Layouts > Shortcuts for Switching Layout: Main shortcuts: (Left Alt+Left Shift); ok;
It appears to work better and better with several reboots.


Fault Resolution:
Fix the sources for "Kde > System Settings > Hardware > Input Devices > Keyboard > Layouts: Shortcuts for Switching Layout";
aka "Kde > System Settings > Hardware > Input Devices > Keyboard > Advanced > Configure keyboard options > Switching to another layout > (Left Alt+Left Shift)".