SUMMARY When opening the KRunner settings via System Settings -> Search -> KRunner or via the settings button in start menu -> configure search plugins you can download new plugins with the "Get New Plugins..." button. While that window is open the System Setting window is in the background. The System Settings window can still be closed regardless and the "Download New Stuff" window (that doesn't have a close button) stays left behind. Its impossible to interact with this window and I needed to kill systemsettings5 to remove this stuck/frozen window. STEPS TO REPRODUCE 1. Open System Settings -> Search -> KRrunner 2. Open the download window to get new plugins 3. Close the System Settings window (which is in the background) OBSERVED RESULT I end up with a leftover window without close button that cant be removed. EXPECTED RESULT The download window gets closed when the parent System Settings window is closed. SOFTWARE/OS VERSIONS Operating System: KDE neon 5.23 KDE Plasma Version: 5.23.4 KDE Frameworks Version: 5.88.0 Qt Version: 5.15.3 Kernel Version: 5.11.4-051104-generic (64-bit) Graphics Platform: X11 Processors: 8 × Intel® Core™ i7-6700K CPU @ 4.00GHz Memory: 31.3 GiB of RAM Graphics Processor: GeForce GTX 1060 6GB/PCIe/SSE2 ADDITIONAL INFORMATION I've tried doing this same procedure opening "Get New...." windows in the System Settings for a few other tools and closing the System Settings window does remove the download window for those. I'm not sure if this is due to the System Settings or an issue with the window framework in general.
Doesn't the window have a "Close" button at the bottom you can click? *** This bug has been marked as a duplicate of bug 437653 ***
(In reply to Nate Graham from comment #1) > Doesn't the window have a "Close" button at the bottom you can click? > > *** This bug has been marked as a duplicate of bug 437653 *** The leftover window does indeed have a close button at the button. But none of the buttons can be used as the window is completely frozen when the parent System Settings window is closed. If the existing button would have closed the window for me I wouldnt have considered it a bug. But needing to kill the process to get rid of an unresponsive window seems like a problem in my opinion. Because of the unresponsive behavior this isn't a duplicate of 437653.
I can reproduce the issue only in QtWidgets-based KCMs like KRunner and Task Switcher. In all QtQuick KCMs, closing the parent window seems to work fine. Moving to the knewstuff framework where the code for this window lives.