SUMMARY Shortcut set up for action "Show Desktop Grid" does not work. STEPS TO REPRODUCE 0. Have a setup with several virtual desktops (System Settings → Desktop Behavior → Virtual Desktops → tab Desktops → Layout) 1. Open System Settings 2. Go to Shortcuts → Global Shortcuts → KWin 3. Type "Show" in the Search box 4. Set up some shortcut (e.g. Ctrl+F8) in the column Global for the action "Show Desktop Grid" 5. Press the shortcut from previous step OBSERVED RESULT Nothing happens EXPECTED RESULT Desktop grid is shown SOFTWARE/OS VERSIONS Linux/KDE Plasma: Kubuntu 18.10 (available in About System) KDE Plasma Version: 5.13.5 KDE Frameworks Version: 5.50.0 Qt Version: 5.11.1
Fixed it on my machine by: 1. Go to System Settings → Display and Monitor → Compositor 2. Get rid of a warning about OpenGL detection 3. Turn "Tearing prevention" from Automatic to Full screen repains 4. Click Apply 5. Turn "Tearing prevention" back to Automatic 6. Click Apply Figured it out using experience from https://bugs.kde.org/show_bug.cgi?id=406703 I do not know why or how operability of shortcuts depends on this. Maybe the compositor was not started despite "Enable compositor on startup" being checked (as per https://bugs.kde.org/show_bug.cgi?id=406703)? From my (stupid user) point of view, this situation definitely seems like a bug: I turn a shortcut on, but the system doesn't even warn me that for the shortcut to work I need some other magic turned on elsewhere.
Global shortcuts allow to configure parts of the system which are not active. You can configure settings for KWin even if you use i3. You can set shortcuts for applications which you don't use. This is - as much as I am aware of - not a bug but a wanted feature. It allows to fix up things. Unfortunately it's not possible to show in every setting that desktop effects are currently not active, because the components don't know it's a desktop effect. I don't see a real issue here.