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diff --git a/testing/web-platform/tests/dom/nodes/DocumentFragment-getElementById.html b/testing/web-platform/tests/dom/nodes/DocumentFragment-getElementById.html
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+++ b/testing/web-platform/tests/dom/nodes/DocumentFragment-getElementById.html
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+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>DocumentFragment.prototype.getElementById</title>
+<link rel="help" href="https://dom.spec.whatwg.org/#dom-nonelementparentnode-getelementbyid">
+<link rel="author" title="Domenic Denicola" href="mailto:d@domenic.me">
+
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<template>
+  <div id="bar">
+    <span id="foo" data-yes></span>
+  </div>
+  <div id="foo">
+    <span id="foo"></span>
+    <ul id="bar">
+      <li id="foo"></li>
+    </ul>
+  </div>
+</template>
+
+<script>
+"use strict";
+
+test(() => {
+  assert_equals(typeof DocumentFragment.prototype.getElementById, "function", "It must exist on the prototype");
+  assert_equals(typeof document.createDocumentFragment().getElementById, "function", "It must exist on an instance");
+}, "The method must exist");
+
+test(() => {
+  assert_equals(document.createDocumentFragment().getElementById("foo"), null);
+  assert_equals(document.createDocumentFragment().getElementById(""), null);
+}, "It must return null when there are no matches");
+
+test(() => {
+  const frag = document.createDocumentFragment();
+  frag.appendChild(document.createElement("div"));
+  frag.appendChild(document.createElement("span"));
+  frag.childNodes[0].id = "foo";
+  frag.childNodes[1].id = "foo";
+
+  assert_equals(frag.getElementById("foo"), frag.childNodes[0]);
+}, "It must return the first element when there are matches");
+
+test(() => {
+  const frag = document.createDocumentFragment();
+  frag.appendChild(document.createElement("div"));
+  frag.childNodes[0].setAttribute("id", "");
+
+  assert_equals(
+    frag.getElementById(""),
+    null,
+    "Even if there is an element with an empty-string ID attribute, it must not be returned"
+  );
+}, "Empty string ID values");
+
+test(() => {
+  const frag = document.querySelector("template").content;
+
+  assert_true(frag.getElementById("foo").hasAttribute("data-yes"));
+}, "It must return the first element when there are matches, using a template");
+</script>