diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index cb936f17478..765b201622d 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -37205,6 +37205,12 @@
     "deleted_reftests": {},
     "items": {
       "testharness": {
+        "html/semantics/interactive-elements/the-dialog-element/dialog-open.html": [
+          {
+            "path": "html/semantics/interactive-elements/the-dialog-element/dialog-open.html",
+            "url": "/html/semantics/interactive-elements/the-dialog-element/dialog-open.html"
+          }
+        ],
         "html/semantics/scripting-1/the-script-element/script-charset-03.html": [
           {
             "path": "html/semantics/scripting-1/the-script-element/script-charset-03.html",
diff --git a/tests/wpt/web-platform-tests/html/semantics/interactive-elements/the-dialog-element/dialog-open.html b/tests/wpt/web-platform-tests/html/semantics/interactive-elements/the-dialog-element/dialog-open.html
new file mode 100644
index 00000000000..4719f63b853
--- /dev/null
+++ b/tests/wpt/web-platform-tests/html/semantics/interactive-elements/the-dialog-element/dialog-open.html
@@ -0,0 +1,30 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>dialog element: open</title>
+<link rel=help href="https://html.spec.whatwg.org/multipage/forms.html#dom-dialog-open">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<dialog id="d1">
+  <p>foobar</p>
+  <button>OK</button>
+</dialog>
+<dialog id="d2" open>
+  <p>foobar</p>
+  <button>OK</button>
+</dialog>
+<script>
+  var d1 = document.getElementById('d1');
+  var d2 = document.getElementById('d2');
+
+  test(function(){
+    assert_false(d1.open);
+    assert_true(d2.open);
+  }, "On getting, the IDL open attribute must return true if the content open attribute is set, and false if it is absent.");
+
+  test(function(){
+    d1.open = true;
+    assert_true(d1.hasAttribute("open"));
+    d2.open = false;
+    assert_false(d2.hasAttribute("open"));
+  }, "On setting, the content open attribute must be removed if the IDL open attribute is set to false, and must be present if the IDL open attribute is set to true.");
+</script>
