<!DOCTYPE html> <html class=reftest-wait> <link rel="help" href="https://drafts.css-houdini.org/css-layout-api/#dom-layoutfragment-data"> <link rel="match" href="green-square-ref.html"> <meta name="assert" content="This test checks that passing something that can't be serialized to the parent triggers a fallback to block layout." /> <style> .test { background: red; width: 100px; } .child { height: 100px; } @supports (display: layout(fallback-fn)) { .test { display: layout(fallback-fn); background: green; } } </style> <script src="/common/reftest-wait.js"></script> <script src="/common/worklet-reftest.js"></script> <div class="test"> <div class="child"></div> </div> <script id="code" type="text/worklet"> registerLayout('fallback-fn', class { async intrinsicSizes() {} async layout(children, edges, constraints, styleMap) { const childFragments = await children.map(child => child.layoutNextFragment()); return {autoBlockSize: 0, childFragments, data: {fn: function() {}}}; } }); </script> <script> importWorkletAndTerminateTestAfterAsyncPaint(CSS.layoutWorklet, document.getElementById('code').textContent); </script> </html>