Mouse stuck on gameboard...

[Snoop]

Is it just me and my trusty macbook-pro or does this happen to everyone ?...

After a game, If I try to exit my browser by clicking the x in the top corner, I have trouble getting my mouse to move any higher than the black background of the quadboard or the lobby... as though it's stuck within the quadradius border... I've discovered that it's alot easier to 'break out' of the trap if I aim my mouse somewhere on the right side of the board instead of the left, but it's really annoying... Why can't I slide my mouse straight up and into the top menu bar of my computer ? Is this just me ? any others experience this and are you using Mac or PC ??