With gdm disabled/replaced by lightdm on our fedora21 workstation, it would be nice if mate-screensaver's "Switch User" functionality worked. But when it is clicked, there is only a brief black screen, and no lightdm re-engagement. It is conceivable that this is because of code in gs-lock-plug.c do_user_switch(), which appears to decide which display-manager to send a message to by the presence of programs in the $PATH. If gdm is on the path (and it will probably be, since it's hard to outright remove on a machine), the gs-lock-plug.c code doesn't seem to want to go to the lightdm option. (The above speculation is based on only eyeballing the source code.)
Hmm, here the screensaver logscreen works well and you have a button to swich the user.
Created attachment 993871 [details] lock-screen
opps, sorry you're right, pressing the button does n't have any effect.
weird, here on f20 baremetal system it works, need to test it later on f21 baremetal.
Ok, the prob is here in the code. https://github.com/mate-desktop/mate-screensaver/blob/master/src/gs-lock-plug.c#L212 I checks first for gdm, than for mdm and at least for lightdm. Means, if gdm is installed on your system it never starts lightdm login. After i removed gdm from my f21 VM the user-switch is working. Try to remove gdm, if you can get rid of gnome-shell for the momment.
The problem is that -some- users on the machine like gnome3/-shell, others prefer mate.
mate-screensaver-1.8.1-2.fc20 has been submitted as an update for Fedora 20. https://admin.fedoraproject.org/updates/mate-screensaver-1.8.1-2.fc20
mate-screensaver-1.8.1-2.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/mate-screensaver-1.8.1-2.fc21
mate-screensaver-1.8.1-2.el7 has been submitted as an update for Fedora EPEL 7. https://admin.fedoraproject.org/updates/mate-screensaver-1.8.1-2.el7
I have set lightdm as 2 condition and gdm as 3 condition, in result that if both DMs are installed lightdm is prefered. I don't expect that a user has both installed and prefer gdm ;)
Package mate-screensaver-1.8.1-2.el7: * should fix your issue, * was pushed to the Fedora EPEL 7 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=epel-testing mate-screensaver-1.8.1-2.el7' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-EPEL-2015-0885/mate-screensaver-1.8.1-2.el7 then log in and leave karma (feedback).
mate-screensaver-1.8.1-2.fc21 has been pushed to the Fedora 21 stable repository. If problems still persist, please make note of it in this bug report.
mate-screensaver-1.8.1-2.fc20 has been pushed to the Fedora 20 stable repository. If problems still persist, please make note of it in this bug report.
mate-screensaver-1.8.1-2.el7 has been pushed to the Fedora EPEL 7 stable repository. If problems still persist, please make note of it in this bug report.