SUMMARY Window thumbnails do not respond to clicks. Most noticeable with vertical task bar. STEPS TO REPRODUCE 1. Change the task bar to vertical task bar 2. Launch multiple applications, some being the same, so windows get grouped. 3. Click on the group windows or hover over the icon so the tile menu appears. 4. Attempt to click on the tile menu and select the window. OBSERVED RESULT Nothing happens. The clicks do not even generate any visual indication of a response. EXPECTED RESULT Window should be selected. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Fedora 33 Workstation (Beta) (available in About System) KDE Plasma Version: 5.19.90 KDE Frameworks Version: 5.75 Qt Version: 5.15.1 ADDITIONAL INFORMATION Using the Wayland session. Windows can be selected using Alt+Tab.
Update: bug still exists on 5.20.3, but slightly different steps to reproduce: 1. Change to vertical task bar. 2. launch multiple applications as described previously. 3. Bring the focus to another application in another group. 4. Click on the tile menu that has a group, in which none of the applications are currently focus. Same thing happens. However, if one of the apps are already in focus, then clicking on the task manager tile will cycle through the windows in the group. To select an app from a tile with no apps in focus, you need to hover over it and click on the correct tile.
*** Bug 440162 has been marked as a duplicate of this bug. ***
The issue seems fixed to me. Please reopen if that's not the case.