I use Xscreensaver, so I uninstall Mate's screensaver. The consequence is that I have the syslog filled with these four messages every time the screensaver starts up. I guess there is more than one problem here.
2025-04-16T09:14:27.670648+02:00 tucano dbus-daemon[5347]: [session uid=1000 pid=5347 pidfd=5] Activated service 'org.mate.ScreenSaver' failed: Failed to execute program org.mate.ScreenSaver: No such file or directory
2025-04-16T09:14:27.671014+02:00 tucano mate-notificati[1387622]: Failed to get dbus connection: Error calling StartServiceByName for org.mate.ScreenSaver: Failed to execute program org.mate.ScreenSaver: No such file or directory
2025-04-16T09:14:27.671069+02:00 tucano mate-notificati[1387622]: g_dbus_proxy_call_sync_internal: assertion 'G_IS_DBUS_PROXY (proxy)' failed
2025-04-16T09:14:27.671093+02:00 tucano org.freedesktop.Notifications[1387622]: free(): double free detected in tcache 2