Im using a External Backup Drive for Timeshift Snapshots… and when im done, i press this unmount button in dolphin and the drive will automatically power down after unmounted.
But since i used Timeshift backup today on my system, this feature no longer works… but i didnt changed anything else on my system, i only restored my snapshot and i had also not much system changed between my the last snapshot… atleast nothing related to unmount stuff or energy settings.
Dolphin can probably only issue the command to power down the device when it’s mounted, but timeshift now automatically unmounts the backup device itself, albeit without sending it the control codes to power down.
I would propose explicitly remounting it in Dolphin after using timeshift and then trying to power it down again from there.
Okay really strange, today i mounted my backup drive and after i click unmount in Dolphin its shutdown as intended… all in all it was just a temporary bug.