will-change-stacking-context-z-index-4.html (941B)
1 <!DOCTYPE html> 2 <title>CSS Test: `will-change: z-index`</title> 3 <link rel="author" title="Oriol Brufau" href="obrufau@igalia.com"> 4 <link rel="help" href="https://www.w3.org/TR/css-will-change/#valdef-will-change-custom-ident"> 5 <link rel="help" href="https://www.w3.org/TR/CSS2/visuren.html#z-index"> 6 <link rel="help" href="https://github.com/w3c/csswg-drafts/issues/11827"> 7 <link rel="match" href="../reference/ref-filled-green-100px-square.xht"> 8 <meta name="assert" content=" 9 `will-change: z-index` doesn't establish a stacking context on a non-positioned block box, 10 because `z-index` doesn't apply in that case. 11 "> 12 <style> 13 .test { 14 will-change: z-index; 15 width: 100px; 16 background: green; 17 } 18 .test::before { 19 content: ""; 20 display: block; 21 position: relative; 22 z-index: -1; 23 height: 100px; 24 background: red; 25 } 26 </style> 27 <p>Test passes if there is a filled green square and <strong>no red</strong>.</p> 28 <div class="test"></div>