The windowing system in Ubuntu has off and on problems for me. I've had to restart X a few times (from another terminal) losing all my work which has been a real pain. What can I do to fix these problems or more gracefully recover when I need to restart X? Forgive any improper terminology, I'm new to Ubuntu.
I'm running Ubuntu 16.04 LTS in VirtualBox. I have 3D Acceleration enabled. I have an Intel i7 running with the Integrated HD Graphics. My host OS is Windows 7.
The problems are all graphical but vary in intensity. Some I can work with and some I can't. The keyboard and mouse still seem to function no matter how bad it glitches out. Here's one example where the window control icons are black.
I've had it sometimes that it will replace title bar drop down menu titles with stretched icon pictures. I've had it get stuck at a black screen. I've also had it get stuck like this.
I have only successfully recovered once and that was by manually telling VirtualBox to reset the display size and everything came back. This hasn't worked in other instances. Running
sudo service lightdm restart always fixes the problem but I also lose my work. There seems to be some small correlation between Chromium (and possibly WebGL) and these issues but they have occurred in other instances.