1 files changed, 60 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/interactive-elements/the-dialog-element/top-layer-display-none.html b/testing/web-platform/tests/html/semantics/interactive-elements/the-dialog-element/top-layer-display-none.html
new file mode 100644
index 0000000000..ba790c1db9
--- /dev/null
+++ b/testing/web-platform/tests/html/semantics/interactive-elements/the-dialog-element/top-layer-display-none.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<html>
+<head>
+<link rel="match" href="top-layer-display-none-ref.html">
+<link rel="help" href="https://fullscreen.spec.whatwg.org/#new-stacking-layer">
+<style>
+dialog {
+    height: 150px;
+    width: 150px;
+    outline: none;
+}
+
+::backdrop {
+    display: none;
+}
+
+.red {
+    background-color: red;
+    top: 200px;
+}
+
+#bottomDialog {
+    background-color: blue;
+    top: 50px;
+    display: none;
+}
+
+#topDialog {
+    background-color: green;
+    top: 100px;
+    left: 50px;
+}
+</style>
+</head>
+<body>
+This tests that a top layer element is not rendered if it, or an ancestor, has display: none.
+It passes if you see a green rectangle stacked on top of a blue rectangle, and see no red rectangles.
+
+<dialog id="hiddenDialog" class="red" style="display: none;"></dialog>
+<div id="container">
+    <div>
+        <dialog id="displayNoneChild1" class="red"></dialog>
+        <dialog id="displayNoneChild2" class="red"></dialog>
+    </div>
+</div>
+<dialog id="bottomDialog"></dialog>
+<dialog id="topDialog"></dialog>
+<script>
+document.getElementById('hiddenDialog').showModal();
+document.getElementById('displayNoneChild1').showModal();
+document.getElementById('container').style.display = 'none';
+document.getElementById('displayNoneChild2').showModal();
+
+// Test that stacking works even if an element is added to the top layer when it has no renderer.
+document.getElementById('bottomDialog').showModal();
+document.getElementById('topDialog').showModal();
+document.getElementById('bottomDialog').style.display = 'block';
+</script>
+</body>
+</html>