SUMMARY
once the program is started, root permissions are requested. At this point it is not possible to close the program until the password is entered. it is impossible to close the window that requires root permissions, and consequently it is impossible to close the other windows as they wait for the user to enter the password to grant permissions.


STEPS TO REPRODUCE
1. Start KDE partition manager from Application Launcher
2. Click Cancel or the "X" in the window asking for root permission

OBSERVED RESULT
the window does not close and permissions are requested again

EXPECTED RESULT
since permissions have not been given the program should close

SOFTWARE/OS VERSIONS
Operating System: Kubuntu 21.10
KDE Plasma Version: 5.24.0
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.2
Kernel Version: 5.17.1-051701-generic (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5700U with Radeon Graphics
Memory: 15,1 GiB of RAM
Graphics Processor: AMD RENOIR

ADDITIONAL INFORMATION
I think it is possible to solve another bug ( https://bugs.kde.org/show_bug.cgi?id=312325 ) at the same time with a simple fix: similarly to G-Parted, before starting the program ask for permissions. if they are guaranteed then start the program otherwise terminate the process. By doing so, the permissions window will always be in the foreground