1 files changed, 39 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/execution-timing/104.html b/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/execution-timing/104.html
new file mode 100644
index 0000000000..95a5a22237
--- /dev/null
+++ b/testing/web-platform/tests/html/semantics/scripting-1/the-script-element/execution-timing/104.html
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html><head>
+        <title> scheduler: adding defer attribute at runtime</title>
+        <script src="/resources/testharness.js"></script>
+        <script src="/resources/testharnessreport.js"></script>
+        <script src="testlib/testlib.js"></script>
+</head>
+<body>
+
+        <div id="test"></div>
+        <div id="log">FAILED (This TC requires JavaScript enabled)</div>
+
+        <script id="defer-script" src="scripts/include-1.js"></script>
+        <script src="scripts/include-2.js"></script>
+
+        <script>
+          var t = async_test();
+
+          t.step(function() {
+            document.getElementById("defer-script").setAttribute("defer", "defer");
+          });
+
+          var ran_defer_check = false;
+
+          document.addEventListener("readystatechange", t.step_func(function () {
+            if (document.readyState == "interactive") {
+              ran_defer_check = true;
+              assert_array_equals(eventOrder, ["external script #1", "external script #2"]);
+            }
+          }), false);
+
+          addEventListener("load", t.step_func(function () {
+            assert_true(ran_defer_check);
+            assert_array_equals(eventOrder, ["external script #1", "external script #2"]);
+            t.done();
+          }), false);
+
+        </script>
+</body></html>