Firefox is a pain to support. Its box model is slightly different than other browser, like shadows take up space and an outline is rendered around the shadow in

Firefox is a pain to support. Its box model is slightly different than other browser, like shadows take up space and an outline is rendered around the shadow instead of aroubd the border. There are other minor things especially on the drag&drop events (in same window, not from outside) but I can't recall the specific.