Created attachment 6846 fpaste --sysinfo Power Manager does not blank/sleep/power off display after x minutes has elapsed. I have to open power manager settings after every reboot and turn off display control and back on again in order to make the screen blank after the set time if I don't the display stays on indefinitely.
I'm also having this issue.
Btw i did a little research, and apparently xfcepm is sending deactivate messages to xscreensaver every 20 seconds.
FYI, according to some info I found out from someone with knowledge of xscreensaver, the powermanager is apparently sending test keypress messages every 20 seconds, which is what's preventing the screensaver from engaging. And this commit appears to be the culprit: https://git.xfce.org/xfce/xfce4-power-manager/commit/?id=a805071464ecf0fee27d59de15620b035d855eb0
Both the commit and the behaviour you're mentioning relate to "Presentation mode", which you can easily enable/disable from the panel plugin. The intention of "presentation mode" is to prevent screensavers from blanking the screen and as there are no common and working standards for screensavers simulating user activity is the fallback. Please uncheck the option and let us know if that resolves your issue.
No more feedback, considered resolved/invalid.