<!DOCTYPE html> <title> Transform animation creates a stacking context even though it's paused on a 100% opacity keyframe </title> <style> span { height: 100px; width: 100px; position: fixed; background: green; top: 50px; } @keyframes Opaque { from, to { opacity: 1 } } #test { width: 100px; height: 100px; background: blue; animation: Opaque 100s paused; } </style> <span></span> <div id="test"></div>