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diff --git a/dom/base/test/test_setInterval_from_start.html b/dom/base/test/test_setInterval_from_start.html
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+++ b/dom/base/test/test_setInterval_from_start.html
@@ -0,0 +1,57 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1252268
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1378394</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1378394">Mozilla Bug 1378394</a>
+
+<script>
+SimpleTest.waitForExplicitFinish();
+
+// Some of our platforms are quite slow.  Use very large time values to
+// try to avoid raciness.
+const burnTimeMS = 5000;
+const intervalTimeMS = 10000;
+
+// The overall interval should include our callback "burn time".  So we
+// expect the delay to be the remaining time.
+const expectedDelayMS = intervalTimeMS - burnTimeMS;
+
+// Allow some margin for error because of slow test platforms.
+const allowedMarginMS = burnTimeMS / 2;
+
+let id;
+let lastEndTime;
+
+function interval()
+{
+  let start = performance.now();
+
+  if (lastEndTime !== undefined) {
+    let delta = start - lastEndTime;
+    ok(delta <= expectedDelayMS + allowedMarginMS,
+       'interval should not fire too late');
+    ok(delta >= expectedDelayMS - allowedMarginMS,
+       'interval should not fire too early');
+    clearInterval(id);
+    SimpleTest.finish();
+    return;
+  }
+
+  while((performance.now() - start) < burnTimeMS);
+
+  lastEndTime = performance.now();
+}
+
+id = setInterval(interval, intervalTimeMS);
+</script>
+
+</body>
+</html>