I am also happy to report that all my fullscreen issues are fixed as of version 0.604 on both of my machines (Ubuntu Linux and SteamOS).
Wonderful
I also thought of setting it to zero instead of gone, but for now I think it's fine. If something changes at the unity-3d-level or the os-level to produce a different default behavior then it's 50-50 that suppressing that default behavior could cause more problems than allowing it.
And glad to hear that you have a mouse that doesn't have the issue you ran into.
What's the model on the mouse that had the problem, and the mouse that didn't? We like to put issues like this (very specific, but high-severity when they do happen) in a FAQ somewhere, and having example model info helps folks diagnose if they're having the same problem.
