SUMMARY When mounting a device that takes a long time mounting (in my case a BTRFS filesystem on LUKS encryption residing on a slow external USB HDD, takes more than 20 seconds to mount), the KDE Plasma disks applets spits an error “Not authorized to mount filesystem”, even though the mount ultimately succeeds. STEPS TO REPRODUCE 1. Connect an external USB device containing a FS that is really long to mount (i.e. a slow USB device containing a BTRFS filesystem on top of LUKS encryption) 2. The disk applet pops-up 3. Click on “mount“ or “mount and open” OBSERVED RESULT - After some time the disks applet spits an error message stating that the user is not authorized to mount the device - Nevetheless, the mount eventually succeeds - But the disks applet will never be aware that the mount ultimately succeeded, thus will never propose an option to unmount/disconnect the device EXPECTED RESULT - I would expect the disk applet to wait for the device to actually mount, and not assume a somewhat long mount time is an error. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Manjaro Linux KDE Plasma Version: Plasma 5.26.3 ADDITIONAL INFORMATION - Same device works good with automounters in Gnome or Cinnamon, only KDE causes an issue.