diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index 78ff1b06ae7..242904f4db2 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -631362,7 +631362,7 @@
    "testharness"
   ],
   "html/semantics/forms/form-submission-0/constructing-form-data-set.html": [
-   "914d61b07898867f2728c2d3cf9d7ad7bdd6aa1b",
+   "8dad6cdd01a43fa17694c67939e8e5a05ab529e2",
    "testharness"
   ],
   "html/semantics/forms/form-submission-0/contains.json": [
diff --git a/tests/wpt/metadata/html/semantics/forms/form-submission-0/constructing-form-data-set.html.ini b/tests/wpt/metadata/html/semantics/forms/form-submission-0/constructing-form-data-set.html.ini
index 956dc69251e..ee52a142650 100644
--- a/tests/wpt/metadata/html/semantics/forms/form-submission-0/constructing-form-data-set.html.ini
+++ b/tests/wpt/metadata/html/semantics/forms/form-submission-0/constructing-form-data-set.html.ini
@@ -7,6 +7,3 @@
 
   [The button cannot be setted if it is not a submitter.]
     expected: FAIL
-
-  [Entries added to "formData" IDL attribute should be submitted.]
-    expected: FAIL
diff --git a/tests/wpt/web-platform-tests/html/semantics/forms/form-submission-0/constructing-form-data-set.html b/tests/wpt/web-platform-tests/html/semantics/forms/form-submission-0/constructing-form-data-set.html
index 914d61b0789..8dad6cdd01a 100644
--- a/tests/wpt/web-platform-tests/html/semantics/forms/form-submission-0/constructing-form-data-set.html
+++ b/tests/wpt/web-platform-tests/html/semantics/forms/form-submission-0/constructing-form-data-set.html
@@ -102,8 +102,12 @@ t1.step(() => {
     e.formData.append('h1', 'vh1');
   });
   let iframe = form.previousSibling;
-  iframe.onload = t1.step_func_done(() => {
+  iframe.onload = t1.step_func(() => {
+    // The initial about:blank load event can be fired before the form navigation occurs.
+    // See https://github.com/whatwg/html/issues/490 for more information.
+    if (iframe.contentWindow.location.href == "about:blank") { return; }
     assert_true(iframe.contentWindow.location.search.indexOf('n1=v1&h1=vh1') != -1);
+    t1.done();
   });
   form.submit();
 });