tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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observe-svg-data-uri-background-image.html (1542B)


      1 <!DOCTYPE HTML>
      2 <meta charset=utf-8>
      3 <title>Largest Contentful Paint: observe image.</title>
      4 <style>
      5  #target {
      6    background-image: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="100" height="50"><rect fill="lime" width="100" height="50"/></svg>');
      7    width: 100px;
      8    height: 50px;
      9  }
     10 </style>
     11 <body>
     12 <script src="/resources/testharness.js"></script>
     13 <script src="/resources/testharnessreport.js"></script>
     14 <script src="resources/largest-contentful-paint-helpers.js"></script>
     15 <script>
     16  async_test(function (t) {
     17    assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
     18    const beforeLoad = performance.now();
     19    const observer = new PerformanceObserver(
     20      t.step_func_done(function(entryList) {
     21        assert_equals(entryList.getEntries().length, 1);
     22        const entry = entryList.getEntries()[0];
     23        let url = 'data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg"';
     24        url += ' width="100" height="50"><rect fill="lime" width="100"';
     25        url += ' height="50"/></svg>';
     26        // green.svg is 100 by 50
     27        const size = 100 * 50;
     28        checkImage(entry, url, 'target', size, beforeLoad);
     29      })
     30    );
     31    observer.observe({type: 'largest-contentful-paint', buffered: true});
     32    t.step_timeout(() => {
     33      assert_unreached("The image should have triggered an LCP entry.");
     34      t.done();
     35    }, 1000);
     36  }, 'Data-URI background SVG image is observable.');
     37 </script>
     38 
     39 <div id="target" width="100" height="50"></div>
     40 </body>