[Desktop] Xscreensaver does not detect when a video is playing

[greenster]

Xscreensaver doesn’t detect when a video is playing, even though I’ve enabled this setting in the Power Settings:




Is there a technical solution that would prevent Xscreensaver from activating the screensaver whilst videos are playing in Haruna or the Vivaldi browser (YouTube videos)?

[die.boer]

please post outputs of :

xscreensaver-command -version

ps aux | grep xscreensaver

loginctl show-session "$XDG_SESSION_ID" -p Type

echo $XDG_SESSION_TYPE

PS: if your on wayland ,xscreensaver won't work reliably/at all , ofcourse...

[greenster]

I use X11 instead of Wayland.

[die.boer]

please also post output of

xscreensaver-demo -version

or

apt policy xscreensaver

just copy/paste commands ,so there's no faulty spaces and stuff

then to post the output here , just select all in the terminal and copy then paste here
please don't show screenshots of the outputs

[greenster]

~$ xscreensaver-demo -version
Unbekannte Option -version
stephan@BlackSnake:~$ apt policy xscreensaver
xscreensaver:
Installiert: 6.08+dfsg1-1ubuntu5
Installationskandidat: 6.08+dfsg1-1ubuntu5
Versionstabelle:
*** 6.08+dfsg1-1ubuntu5 500
500 http://archive.ubuntu.com/ubuntu resolute/universe amd64 Packages
100 /var/lib/dpkg/status

[die.boer]

run this in terminal and leave it running

dbus-monitor "interface='org.freedesktop.ScreenSaver'"

Then:
Start playing a video in Haruna.
Stop it.
Play a YouTube video in Vivaldi.

If everything is working, you should see messages containing Inhibit when playback starts and UnInhibit when it ends.
If nothing appears at all, then the applications aren't requesting inhibition, which would explain why XScreenSaver activates.
Also , Are you using the Snap version of Vivaldi, the DEB package from Vivaldi's website, or the Flatpak?
check with

which vivaldi

or

apt policy vivaldi-stable

Likewise for Haruna:

apt policy haruna

or

flatpak list | grep -i haruna

Whether they're installed as native packages, Flatpaks, or Snaps can affect how idle inhibition is handled.

PS: like any command in terminal that keeps running , you can stop it with ctrl+c , in case you didn't know

[greenster]

~$ which vivaldi
/usr/bin/vivaldi
stephan@BlackSnake:~$ apt policy vivaldi-stable
vivaldi-stable:
Installiert: 8.0.4033.54-1
Installationskandidat: 8.0.4033.54-1
Versionstabelle:
*** 8.0.4033.54-1 500
500 https://repo.vivaldi.com/stable/deb stable/main amd64 Packages
100 /var/lib/dpkg/status
stephan@BlackSnake:~$ apt policy haruna
haruna:
Installiert: 1.7.1-1ubuntu3
Installationskandidat: 1.7.1-1ubuntu3
Versionstabelle:
*** 1.7.1-1ubuntu3 500
500 http://archive.ubuntu.com/ubuntu resolute/universe amd64 Packages
100 /var/lib/dpkg/status
stephan@BlackSnake:~$ flatpak list | grep -i haruna


I use the .deb package from Vivaldi.

[die.boer]

run this in terminal and leave it running
Code:

dbus-monitor "interface='org.freedesktop.ScreenSaver'"
Then:
Start playing a video in Haruna.
Stop it.
Play a YouTube video in Vivaldi.

could you do that?
Copy everything that appears in the terminal (even if it's nothing).
That will tell us whether the applications are asking the desktop to inhibit the screensaver.

[die.boer]

also if you can tell me what is your xscreensaver timeout

xscreensaver-command -time

set to , we can run a little command to verify that xscreensaver-systemd itself is working

[greenster]

could you do that?
Copy everything that appears in the terminal (even if it's nothing).
That will tell us whether the applications are asking the desktop to inhibit the screensaver.

~$ dbus-monitor "interface='org.freedesktop.ScreenSaver'"
signal time=1782648784.170241 sender=org.freedesktop.DBus -> destination=:1.110 serial=2 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameAcquired
string ":1.110"
signal time=1782648784.170258 sender=org.freedesktop.DBus -> destination=:1.110 serial=4 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameLost
string ":1.110"
method call time=1782648802.582539 sender=:1.111 -> destination=org.freedesktop.ScreenSaver serial=38 path=/org/freedesktop/ScreenSaver; interface=org.freedesktop.ScreenSav
er; member=UnInhibit
uint32 4294967295
method call time=1782648802.767976 sender=:1.111 -> destination=org.freedesktop.ScreenSaver serial=55 path=/org/freedesktop/ScreenSaver; interface=org.freedesktop.ScreenSav
er; member=Inhibit
string "org.kde.haruna"
string "Mediendatei wird abgespielt"
method call time=1782648840.101197 sender=:1.84 -> destination=org.freedesktop.ScreenSaver serial=469 path=/org/freedesktop/ScreenSaver; interface=org.freedesktop.ScreenSav
er; member=Inhibit
string "/usr/bin/vivaldi-stable"
string "Video Wake Lock"
method call time=1782648856.967814 sender=:1.84 -> destination=org.freedesktop.ScreenSaver serial=500 path=/org/freedesktop/ScreenSaver; interface=org.freedesktop.ScreenSav
er; member=UnInhibit
uint32 15689

[greenster]

also if you can tell me what is your xscreensaver timeout

xscreensaver-command -time

set to , we can run a little command to verify that xscreensaver-systemd itself is working

$ xscreensaver-command -time
XScreenSaver 6.08: screen non-blanked since Sun Jun 28 14:09:17 2026 (hack #34)
stephan@BlackSnake:~$

[die.boer]

ok , both Haruna and Vivaldi are requesting inhibition exactly as they should. so nothing wrong there.
looks like xscreensaver-systemd isn't actually forwarding the inhibit request to XScreenSaver.
next run

journalctl --user --since "15 minutes ago" | grep xscreensaver

if that produces nothing,try

journalctl --since "15 minutes ago" | grep xscreensaver

we looking for any errors from xscreensaver-systemd.

Also, check whether the helper can talk to XScreenSaver

xscreensaver-command -watch

leave it running ,then start a video in Haruna.
Normally, if the helper is working, you should see events such as DEACTIVATE, UNBLANK, or periodic activity while the video is playing.

Also ,did you install XScreenSaver from the Ubuntu repositories, or did you compile/install it from the official XScreenSaver website?

PS: let's try above 1st to see , then we can run the little "test"

we can run a little command to verify that xscreensaver-systemd itself is working

[die.boer]

another piece of info that's probably of relevance ...
Plasma already provides:
screen locking (KScreenLocker)
monitor power management (PowerDevil)
idle inhibition
media playback detection
presentation mode
Wayland support

Those components are all designed to work together.

So installing XScreenSaver means you're effectively replacing one piece of Plasma with another program that wasn't designed specifically for Plasma.
Plasma also wants to control those same things.

So you end up with two systems trying to manage:
idle detection
monitor power
locking
inhibition

That can lead to odd interactions like the one you're troubleshooting.

Any particular reason you want/need Xscreensaver ?

---