Shows desktop instead of blank screen

[Safari77]

When locking screen, either timeout or mate-screensaver-command --lock, screen does not blank, but instead shows desktop image at the time of locking. When I press any key, the password prompt comes up and the configured lockscreen image is shown OK.
Mate-desktop and mate-screensaver 1.16.0, gtk 3.22.0.

org.mate.power-manager lock-use-screensaver true
org.cinnamon.SessionManager autostart-blacklist ['gnome-settings-daemon', 'gnome-fallback-mount-helper', 'gnome-screensaver', 'mate-screensaver', 'mate-keyring-daemon', 'indicator-session', 'gnome-initial-setup-copy-worker', 'gnome-initial-setup-first-login', 'gnome-welcome-tour', 'xscreensaver-autostart', 'nautilus-autostart', 'caja', 'xfce4-power-manager']
org.mate.screensaver logout-enabled false
org.mate.screensaver lock-enabled true
org.mate.screensaver embedded-keyboard-enabled false
org.mate.screensaver logout-delay 120
org.mate.screensaver idle-activation-enabled true
org.mate.screensaver themes @as []
org.mate.screensaver logout-command ''
org.mate.screensaver embedded-keyboard-command ''
org.mate.screensaver mode 'blank-only'
org.mate.screensaver power-management-delay 30
org.mate.screensaver lock-delay 0
org.mate.screensaver cycle-delay 10
org.mate.screensaver lock-dialog-theme 'default'
org.mate.screensaver status-message-enabled true
org.mate.screensaver user-switch-enabled true
org.mate.SettingsDaemon.plugins.media-keys screensaver '<Control><Alt>l'

[bobi1024]

Same here.
debian testing
mate 1.16 compiled from source
mate-screensaver compiled from source 1.16 release
libgtk 3.21.5-3

[gradinaruvasile]

Same here. Debian testing with Mate 16.0 from unstable, .
I have 2 monitors, one of the laptop display and the other is an external display. Intel Skylake graphics.
One of the monitors (where the cursor is when locking) shows the lock screen as it should, but the other monitor remains frozen at the last image it had.
With mate 14.2 it was working ok.
I had to resort to xscreensaver as a stopgap measure.

[gradinaruvasile]

Well. I uninstalled mate-screensaver, started xscreensaver then installed mate-screensaver again and now it is working as it should.
Edit:
My mistake, i installed the 1.14 screensaver (default for Debian testing) instead of the 1.16 version.
1.16 is still not working well.

$ apt-cache policy mate-screensaver
mate-screensaver:
  Installed: 1.16.0-1
  Candidate: 1.16.0-1
  Version table:
 *** 1.16.0-1 500
        500 http://ftp.debian.org/debian testing/main amd64 Packages
          2 http://ftp.debian.org/debian unstable/main amd64 Packages
        100 /var/lib/dpkg/status

mate-screensaver-command --version
mate-screensaver-command 1.16.0

[arehtykitna]

@raveit65 mate-screensaver-1.16-01.fc25 is affected by this bug. All other screensavers in the package appear to work okay.

[fredo-m]

Hi,
I had the same bug, I had opened a bug report on Debian's bug tracker:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=841642

According to my tests, the bug is only for "blank screen" screen saver, the others work.
Is this the same problem that Caja had with the management of desktop background image?

Regards.

[pwaller]

I thought I'd have a go at bisecting this on debain sid. Built version 0.14 from source, but the bug persists there, making me think it may instead be a problem with the x server or something else, rather than mate-screensaver per-se. @gradinaruvasile can you confirm that just changing to 0.14 fixes the issue? (And nothing else was changed?) What do you need to change to make it work?

[gradinaruvasile]

@pwaller
Unfortunately i don't have time to test much, but what i observed is the following:
Using versions up to 1.14.2 i had no issues like this. When 1.16 was in unstable i upgraded to it and i saw this issue. I downgraded to 1.14.2, it went away. I did this on 2 separate computers and both behaved the same way (both had 2 monitors). So at that point the version of the screensaver was the deciding factor. Since then many components were upgraded and 1.14 is not available anymore.
Also, as @fredo-m pointed out, this bug does not manifest when using other themes than "blank screen" (i now use the matrix theme and it's ok but i would still like to have a real screensaver).
Edit:
It works like this:
When the screensaver kicks in, it does NOT cover any monitors by default with anything. The screen only freezes. If there is some input activity the last used monitor will be covered with the password screen, but the other monitor is not covered by anything.
If the power management monitor off timeout is reached, dpms kicks in and if you press a buttion/move mouse only the last screen is resumed and it is covered with the password screen. Secondary is black.
I would like to see the screensaver with dpms possibilities, like xscreensaver does and we would be able to set to instant dpms.

[raveit65]

It is only a problem with blank screensaver theme. I have 2 reports about in fedora 25.
https://bugzilla.redhat.com/show_bug.cgi?id=1398831
https://bugzilla.redhat.com/show_bug.cgi?id=1397900
But i have m-s gtk3 also running on fedora 24, so i can check if it makes a different with another xorg-server version.

[monsta]

Now I have this as well... with GTK+ 3.22.5 and blank theme.

[monsta]

Ok, fixed by #110.