I updated Firefox Tweaks and Fixes and Styles and Things with a section on how to enlarge the Firefox user interface (UI) on small displays. In my case i use a laptop with a 17 in., 1080p display and by default everything is way too small. Making the Firefox UI and web pages look bigger can be a little tricky and cause unwanted side effects however. In the article i offer a tip which seems to be the best way to accomplish this with the least amount of problems. The tip also includes information for making the UI for Firefox's developer tools bigger.