Comment 38 for bug 1604313

This bug is still in 16.04.

I seem to be able to work around this issue by closing the display while in the bug. Let the display orientation update so only the external monitor(s) is turned on, then undock the computer and finally open the display and close it again.

But undocking the computer with the display open and then trying to make the computer sleep will always make it lockup so that the cursor is the only thing that's responsive.