<!DOCTYPE HTML> <!-- Tests that setting a fixed top margin in the compositor results in the margin being applied to an element fixed to the top. The fixed margin is specified as a test-pref in reftest.list. The purpose of the fixed margin is to compensate for the transform that the dynamic toolbar applies to the entire content area. We don't have a way of simulating that transform in a reftest, so the fixed margin in isolation will cause the fixed element to be offset from the top of the screen, and in the ref page we use a regular CSS "margin-top" to match the rendering. --> <html> <meta name="viewport" content="width=device-width"> <style> html { scrollbar-width: none; } #scrolled { height: 2000px; width: 100%; } #fixed { width: 100%; height: 200px; position: fixed; top: 0; background: red; } </style> <body> <div id="scrolled"></div> <div id="fixed"></div> </body> </html>