Comment 0 for bug 1574617

I have an external monitor connected to my Thinkpad as an extended desktop. On Ubuntu 15.10 it worked fine but in 16.04 it 'crashes' under certain conditions.
When you move mouse from the external monitor across and hover over the laptop screen the external monitor blanks out. It sometimes 'comes back to life' after a few seconds. The monitor also sometimes drops out of it's own accord and appears to be random.
The laptop isn't disconnecting from the monitor as if you take a screenshot you'll still see your extended desktop with windows open but the monitor is no longer detecting a signal from the laptop.
To 'fix' either:
1. Run startx
2. Change something in the display menu (ie. the resolution), basically anything to force the laptop to 'update' the desktop and rescale
3. log out/shutdown/restart

To be clear/Tldr; - this is not an issue with the monitor or cable, it still works fine with other laptops and had been fine up until the upgrade to 16.04. (When it initially started happening I assumed it was a cable issue so I have swapped out the cable a couple of times) and the monitor does not 'disconnect': just blanks out.

Hardware - Thinkpad T410 (Intel Ironlake)

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: evince 3.18.2-1ubuntu4
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Apr 25 13:26:31 2016
EcryptfsInUse: Yes
InstallationDate: Installed on 2015-09-21 (216 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_GB.UTF-8
 SHELL=/usr/bin/zsh
SourcePackage: evince
UpgradeStatus: Upgraded to xenial on 2016-04-22 (3 days ago)