Same problem on my laptop, started right after upgrade from 15.10 to 16.04. Happens right after I plug external monitor to to HDMI socket, system freezes and not responding to any actions from keyboard and touchpad. I'm using Intel® HD Graphics 520.
Same problem on my laptop, started right after upgrade from 15.10 to 16.04. Happens right after I plug external monitor to to HDMI socket, system freezes and not responding to any actions from keyboard and touchpad. I'm using Intel® HD Graphics 520.