Utility-CSS sites stop stacking their lines on top of each other
A CSS framework's docs is the most popular way to style modern websites, and its current version sets the gap between lines of text with a small sum that comes out as a plain number, meaning "this many times the text size". The engine read that number as a size in pixels, so on Utility-CSS sites every line of a code example (and any text styled the same way) was drawn almost exactly on top of the line before it. It now reads it the way the standard says and the reference browser does, and we checked the result against the reference browser on the live a CSS framework's docs documentation.