Great! Rated 5 out of 5 stars
I'm searching for an extension like this from many many time!!!
It is already usable but it needs some more work to be fixed and improved!
I've a problem:
I can't use ff in a resized windows, when i select the resize button the windows disappear.
And a request!
Could you implement an option to see a small border(1 or 2 px) around the the window.
Great job, keep on this way! ;)