I'm also experiencing this issue on a Thinkpad T480 (20L5) connecting to a ThinkPad Thunderbolt 3 Dock. It worked fine on Ubuntu 18.04 LTS until about a week ago, when I started experiencing this issue and the bug in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813663 more or less simultaneously.
The latter issue was resolved by downgrading to kernel 4.15.0-43, and later upgrading to 4.15.0-45. This one remained a problem even after upgrading to Ubuntu 18.10 and kernel 4.18.0-14. I can confirm that installing kernel 4.20.6-042006 via Ukuu fixes it. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1752165 Title: TB16 dock freezes X on hotplug when used with external displays To manage notifications about this bug go to: https://bugs.launchpad.net/dell-sputnik/+bug/1752165/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
