Description of problem: The screen saver is not displayed on MATE Desktop because of the last line of the file /etc/xdg/autostart/xscreensaver-autostart.desktop (OnlyShowIn=X-NODEFAULT;) which prevents the start of the daemon on MATE Desktop when neither gnome-screensaver nor mate-screensaver are installed on the system: $ cat /usr/libexec/xscreensaver-autostart #!/usr/bin/sh # Don't launch xscreensaver if gnome-screensaver # is installed if [ -x /usr/bin/gnome-screensaver ] ; then exit 0 ; fi if [ -x /usr/bin/mate-screensaver ] ; then exit 0 ; fi exec xscreensaver -nosplash
X-NODEFAULT is actually on purpose (i.e. default to now shown on any desktop environment - but still useful in LXDE, for example). I gave up determining in which DE xscreensaver should be launched via desktop entry. This is never-ending discussion. Other people may have different opinition than yours. For now, I don't intend to change this behavior.
I could not find your free interpretation of OnlyShowIn key in any of the freedesktop specifications. https://specifications.freedesktop.org/desktop-entry-spec/latest/ar01s06.html
X-FOO is extension https://specifications.freedesktop.org/desktop-entry-spec/latest/ar01s12.html Anyway, for this bug, I don't intend to enable this on MATE.
Again, I gave up deciding in which desktop environment xscreensaver should be auto-started. This is never-ending discussion. So I decided not to enable autostart by default. Still some DE can make use of this desktop file even if autostart is not enabled by default. So I've put X-FOO which is 4 supported *not* to correspond to any DE, but nevertheless create this desktop file. So even if I may change OnlyShowIn value, I am not going to enable this on MATE, GNOME, XFCE or so.
(In reply to Mamoru TASAKA from comment #3) > X-FOO is extension > https://specifications.freedesktop.org/desktop-entry-spec/latest/ar01s12.html > Anyway, for this bug, I don't intend to enable this on MATE. You can X-FOO or similar field for personal use, no for shipping it into a software distribution, the text below is extracted from the link "If one particular party wishes to add a field for personal use, they should prefix the key with the string X-PRODUCT, e.g. X-NewDesktop-Foo, following the precedent set by other IETF and RFC standards."
(In reply to Mamoru TASAKA from comment #3) > X-FOO is extension > https://specifications.freedesktop.org/desktop-entry-spec/latest/ar01s12.html > Anyway, for this bug, I don't intend to enable this on MATE. You can use X-FOO or similar field for personal use, no for shipping it into a software distribution, the text below is extracted from the link "If one particular party wishes to add a field for personal use, they should prefix the key with the string X-PRODUCT, e.g. X-NewDesktop-Foo, following the precedent set by other IETF and RFC standards."
This is not related to "cannot be enabled on MATE", anyway. Please stop.
*** Bug 1918631 has been marked as a duplicate of this bug. ***