Thank you for reporting this problem. Could you try and run this command in a terminal before you plug in the external monitor and upload the resulting file (udevadm.log) here (after you reboot)?
udevadm monitor --property > ~/udevadm.log
Hopefully, there will be some clue to what is going on in this file.
Thank you for reporting this problem. Could you try and run this command in a terminal before you plug in the external monitor and upload the resulting file (udevadm.log) here (after you reboot)?
udevadm monitor --property > ~/udevadm.log
Hopefully, there will be some clue to what is going on in this file.