As stated in bug 1813831 thread, the issue is related to a change in the graphic driver's DPMS sequence. It was introduced in 4.15.0-44, and reverted in 4.15.0-45 made available for testing in the other bug's thread.
Meaning that it's not related to thunderbolt docks, nor docks at all, but to the display driver initializing the screen(s) through DPMS. My Dell 9370 shows the issue on each boot with -44 even when not connected to any external peripheral / dock / display, just with its internal screen. The issue is totally gone with -45. The DPMS change revert was already committed to upstream kernel patch train. -- 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
