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diff --git a/dom/performance/tests/test_performance_paint_timing_helper.html b/dom/performance/tests/test_performance_paint_timing_helper.html
new file mode 100644
index 0000000000..c05b38cac0
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+++ b/dom/performance/tests/test_performance_paint_timing_helper.html
@@ -0,0 +1,65 @@
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<!DOCTYPE HTML>
+<html>
+    <!--
+      https://bugzilla.mozilla.org/show_bug.cgi?id=1518999
+    -->
+    <head>
+        <title>Test for Bug 1518999</title>
+        <meta http-equiv="content-type" content="text/html; charset=UTF-8">
+    </head>
+    <body>
+        <div id="main"></div>
+        <div id="image"></div>
+        <div id="test">
+            <script class="testbody" type="text/javascript">
+             async function runTest() {
+                const paintEntries = performance.getEntriesByType('paint');
+                opener.is(paintEntries.length, 0, "No paint entries yet");
+
+                const img = document.createElement("img");
+                img.src = "http://example.org/tests/dom/performance/tests/logo.png";
+
+                img.onload = function() {
+                  function getAndTestEntries(runCount) {
+                    function testEntries(entries) {
+                      opener.is(entries.length, 1, "FCP Only returns");
+                      opener.is(entries[0].entryType, "paint", "entryType is paint");
+                      opener.is(entries[0].name, "first-contentful-paint",
+                                "Returned entry should be first-contentful-paint" );
+                      const fcpEntriesGotByName =
+                          performance.getEntriesByName('first-contentful-paint');
+                      opener.is(fcpEntriesGotByName.length, 1, "entries length should match");
+                      opener.is(entries[0], fcpEntriesGotByName[0], "should be the same entry");
+                      opener.done();
+                    }
+                    const entries = performance.getEntriesByType('paint');
+                    if (entries.length < 1) {
+                      if (runCount < 4) {
+                        opener.SimpleTest.requestFlakyTimeout("FCP is being registered asynchronously, so wait a bit of time");
+                        setTimeout(function() {
+                          getAndTestEntries(runCount + 1);
+                        }, 20);
+                      } else {
+                        opener.ok(false, "Unable to find paint entries within a reasonable amount of time");
+                        opener.done();
+                      }
+                    } else {
+                        testEntries(entries);
+                    }
+                  }
+                  getAndTestEntries(1);
+                }
+                document.body.appendChild(img);
+             }
+             window.onload = function() {
+                runTest();
+             }
+            </script>
+        </div>
+        </div>
+    </body>
+</html>