1 files changed, 23 insertions, 0 deletions
diff --git a/testing/web-platform/tests/shadow-dom/focus/delegatesFocus-tabindex-change.html b/testing/web-platform/tests/shadow-dom/focus/delegatesFocus-tabindex-change.html
new file mode 100644
index 0000000000..f159c22164
--- /dev/null
+++ b/testing/web-platform/tests/shadow-dom/focus/delegatesFocus-tabindex-change.html
@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<link rel=author href="mailto:jarhar@chromium.org">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<body>
+<script>
+test(() => {
+  const host = document.createElement('div');
+  document.body.appendChild(host);
+
+  const shadowRoot = host.attachShadow({mode: 'open', delegatesFocus: true});
+
+  const shadowInput = document.createElement('input');
+  shadowRoot.appendChild(shadowInput);
+
+  host.focus();
+  assert_equals(document.activeElement, host, 'The shadow host should be focused.');
+
+  host.setAttribute('tabindex', '0');
+  assert_equals(document.activeElement, host, 'The shadow host should remain focused after changing tabindex.');
+}, 'Setting tabindex on the shadow host of a focused element with delegatesFocus should not change focus.');
+</script>