1 files changed, 30 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/rendering/the-details-element/auto-expand-details-text-fragment.html b/testing/web-platform/tests/html/rendering/the-details-element/auto-expand-details-text-fragment.html
new file mode 100644
index 0000000000..321d82c02d
--- /dev/null
+++ b/testing/web-platform/tests/html/rendering/the-details-element/auto-expand-details-text-fragment.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>beforematch fired on ScrollToTextFragment</title>
+<link rel="author" title="Joey Arhar" href="mailto:jarhar@chromium.org">
+<link rel="help" href="https://github.com/WICG/display-locking">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+
+<script src="/common/utils.js"></script>
+<script src="/scroll-to-text-fragment/stash.js"></script>
+
+<script>
+promise_test(t => new Promise((resolve, reject) => {
+  const key = token();
+  test_driver.bless('Open a scroll to text fragment URL', () => {
+    window.open(
+      `resources/auto-expand-details-text-fragment.html?key=${key}#:~:text=foo`,
+      '_blank',
+      'noopener');
+  });
+  fetchResults(key, resolve, reject);
+}).then(results => {
+  assert_true(results.detailsHasOpenAttribute,
+    'The matching closed details element should be open.');
+  assert_true(results.pageYOffsetAfterRaf > 0,
+    'The page should be scrolled down to the match.');
+}), 'Verifies that the beforematch event is fired on the matching element of a ScrollToTextFragment navigation.');
+</script>