<!DOCTYPE html> <link rel="help" href="https://wicg.github.io/layout-instability/" /> <script src="/resources/testharness.js"></script> <script src="/resources/testharnessreport.js"></script> <script src="resources/util.js"></script> <div id="multicol" style="position:relative; columns:5; column-gap:0; column-gap:0; width:500px; height:1px;"> <div style="contain:size; height:100px; background:hotpink;"></div> <div style="contain:size; height:100px; background:hotpink;"></div> <div style="contain:size; height:100px; background:hotpink;"></div> <div style="contain:size; height:100px; background:hotpink;"></div> <div style="contain:size; height:100px; background:hotpink;"></div> </div> <script> promise_test(async () => { const watcher = new ScoreWatcher; await waitForAnimationFrames(2); multicol.style.top = '100px'; const expectedScore = computeExpectedScore(500 * (100 + 100), 100); await watcher.promise; assert_equals(watcher.score, expectedScore); }, 'Move multicol container with overflow'); </script>