First of all, Iron is an awesome browser, especially with the ad blocker. I'm glad you all are taking user privacy seriously.
Now on to the real purpose of this reply:
When Iron 2 is maximized, the tab bar appears to be pushed beyond the boundary of the screen.
See this screenshot:
And it's not just a cropped image, I assure you.
Shot was taken on Windows Vista Home Premium (Service Pack 1).