When I click Minecraft, Bootstrap 5 appears and goes through the normal starting process. After Bootstrap says "Starting Launcher.", the Bootstrap window does one of these:
1. Disappears.
2. Freezes and will not let me do anything. The window's title bar is not selected, and will not let me do anything but minimize it.
I started noticing this problem when I upgraded from Ubuntu 15.04 to Ubuntu 15.10.
I have an Intel core i5 processor. I have a 1920x1080 screen and Intel Mobile Graphics. I am using a Dell XPS 13. (older version)