CloudCompare fails to launch with error: “QXcbConnection: Could not connect to display :0”

In the last week, CloudCompare has suddenly stopped launching. When trying to launch via desktop icon, nothing happens. When trying to launch via commandline (e.g. $ cloudcompare.CloudCompare) nothing happens and I get the following error:

Trying to launch CloudCompare with sudo/as root user returns a slightly different error message:

Having looked around Github, here and various other forums, this seems to be a problem that people have encountered with other programs that use Qt and/or OpenGL (see 1, 2, 3). I also realise that this isn't really enough information to debug the problem, so if there is any other diagnostic info I can/should provide, let me know and I will add it.

My Environment

• OS & Version: Ubuntu 14.04 LTS

• CC Version: v2.8.1 (latest)

• Graphics card: Intel Haswell Mobile

• Qt version: 5.2.1