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<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=1776790
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  <meta charset="utf-8">
  <title>Test for Bug 1776790</title>
  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
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<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1776790">Mozilla Bug 1776790</a>
<p id="display"></p>
<div id="content" style="display: none">

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<pre id="test">
<script type="application/javascript">
/* global TestInterfaceLength */

add_task(async function init() {
  await SpecialPowers.pushPrefEnv({set: [["dom.expose_test_interfaces", true]]});
});

/** Test for Bug 1776790 **/
add_task(function test_interface_length() {
  is(TestInterfaceLength.length, 1, "TestInterfaceLength.length");
});

</script>
</pre>
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