I have the almost same issue with my Dell latitude E5520 plugged into the dock station WD15. This issue occurred after the latest linux kernel upgrade (to 4.15.044.46). At startup all my screen are correctly initialized. But when my computer enter in power-save mode (i.e screen become black after a while), my laptop is not responding anymore. I need to restart it. Notice that the "magic keys" works : the sequence alt+sys+[s,u,b] restart the computer.
** Changed in: linux (Ubuntu Bionic) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1813663 Title: External monitors does not work anymore 4.15.0-44 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813663/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs