Try New Technology

Suddenly after an about back in November I noticed the monitors no longer going to sleep. After digging around I found that the System Settings > Power Management > Energy Savings was throwing errors (I think the exact error was “kde power management service not running /usr/lib/org_kde_powerdevil”) about the service not running and therefor the panels would not be interacted with and all of the setting were disabled. Searching over a couple weeks finally came up with a solution thanks to a post on the Arch Linux BBS (ref: [SOLVED] KDE plasma power management not working / starting):

• Edit /usr/lib/systemd/user/plasma-powerdevil.service — I used Kate since it will correct sudo when saving
• Find the “TimeoutSec=” variable (line 10) — I changed mine to “10sec“
• Logoff or Reboot
• System Settings > Power Management > Energy Savings should now be working as expected

NOTE: I ended up applying this fix a few times due to an update seeming breaking things again. It has been “holding” fine with all the updates through December though. More details can be found on the Manjaro forums here.