I found small bug but it's quite irritating when you are working on multiple desktops (e.g. laptop and secondary monitor).
Sublime stores last window position and size in a configuration file under window/position key.
The problem is in the fact that on multiple desktops the seconday window can have big value, e.g.:
<position>0,0,1,-32000,-32000,-1,-1,1036,1280,0,2572</position> from my session file.
When Sublime is running on only one monitor it uses values saved before.
And the problem occured when you are goingo to restore window - it simply disappearing.
I think it would be good idea to validate these parameters on start and to correct them to proper values if they are invalid.