There is a bug in the mesa-libGL library used in the Debian derived Linux’s presently that may either break your ability to connect via x2go or break some desktop functionality.  This is because when the screen size is queried the library is incorrectly returning a rectangle of 0x0.  I know the developers are aware but no idea how long it will take to be fixed.

     In the meantime you can try a different desktop or use the web terminal or graphics console function under web apps to get a remote desktop.