in #lubuntu-devel Krytarik suggested I try an older version <krytarik> guiverc: From a quick web search and given the behavior, it still seems likely that xscreensaver is at fault there though. Could downgrade the packages you've got manually to the previous version here and test if it's the same with that too: https://launchpad.net/ubuntu/+source/xscreensaver/5.36-1ubuntu1/+build/12357850
I installed that version guiverc@d960-ubu2:~$ apt-cache policy xscreensaver xscreensaver: Installed: 5.36-1ubuntu1 Candidate: 5.42+dfsg1-1ubuntu1 Version table: 5.42+dfsg1-1ubuntu1 500 500 http://ftp.iinet.net.au/pub/ubuntu disco/universe amd64 Packages *** 5.36-1ubuntu1 500 500 http://old-releases.ubuntu.com/ubuntu zesty/universe amd64 Packages 100 /var/lib/dpkg/status guiverc@d960-ubu2:~$ logged out & re-tried, still same effect (I can view one screen which updates its windows [htop] and screensaver runs on other). I then rebooted & retried & got same result -- screens dim for a second (a very nice effect) then one display resumes it's display of htop/hexchat etc & other shows xscreensaver... -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1814490 Title: lubuntu 19.04 xscreensaver runs on single display, other display continues normally To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xscreensaver/+bug/1814490/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs