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diff --git a/testing/web-platform/tests/element-timing/background-image-data-uri.html b/testing/web-platform/tests/element-timing/background-image-data-uri.html
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index 0000000000..9722463742
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+++ b/testing/web-platform/tests/element-timing/background-image-data-uri.html
@@ -0,0 +1,39 @@
+<!DOCTYPE HTML>
+<meta charset=utf-8>
+<title>Element Timing: observe element with inline background image</title>
+<body>
+<style>
+body {
+  margin: 0;
+}
+#target {
+  width: 100px;
+  height: 50px;
+  background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKAQMAAAC3/F3+AAAABGdBTUEAALGPC/xhBQAAACBjSFJNAAB6JgAAgIQAAPoAAACA6AAAdTAAAOpgAAA6mAAAF3CculE8AAAABlBMVEX/AAD///9BHTQRAAAAAWJLR0QB/wIt3gAAAAtJREFUCNdjYMAHAAAeAAFuhUcyAAAAJXRFWHRkYXRlOmNyZWF0ZQAyMDE5LTA0LTA1VDIwOjA4OjQxKzAyOjAwPa6EZwAAACV0RVh0ZGF0ZTptb2RpZnkAMjAxOS0wNC0wNVQyMDowODo0MSswMjowMEzzPNsAAAAASUVORK5CYII=);
+}
+</style>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/element-timing-helpers.js"></script>
+<script>
+  let beforeRender = performance.now();
+  async_test(function (t) {
+    assert_implements(window.PerformanceElementTiming, "PerformanceElementTiming is not implemented");
+    const observer = new PerformanceObserver(
+      t.step_func_done(function(entryList) {
+        assert_equals(entryList.getEntries().length, 1);
+        const entry = entryList.getEntries()[0];
+        // Only the first characters of the data URI are included in the entry.
+        const uriPrefix = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKAQMAAAC3/F3+AAAABGdBTUEAALGPC/xhBQAAACBjSFJNAA';
+        checkElementWithoutResourceTiming(entry, uriPrefix, 'my_div', 'target',
+            beforeRender, document.getElementById('target'));
+        // The background image is a red square of length 10.
+        checkRect(entry, [0, 100, 0, 50]);
+        checkNaturalSize(entry, 10, 10);
+      })
+    );
+    observer.observe({entryTypes: ['element']});
+  }, 'Element with elementtiming attribute and inline background image is observable.');
+</script>
+<div id='target' elementtiming='my_div'></div>
+</body>