With the current setup, I didn't manage to reproduce the problem yet today. Here's the debug log that you asked that includes booting with the thunderbolt connected, then disconnecting and reconnecting - all completing successfully.
** Attachment added: "okconnect.log" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1856161/+attachment/5317699/+files/okconnect.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1856161 Title: Thunderbolt dock fails to connect USB devices To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1856161/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs