Good 4 Web Designers Rated 4 out of 5 stars

I do a bit of web development, and it's useful for checking to see how your page would look within smaller resolutions (as most people don't have a 23-inch flatscreen!)

One idea may be to have buttons that allow you to click to resize your browser to a certain size (say 1024x768).

This review is for a previous version of the add-on (0.53).