Bug 2078352 - Selenium test 4_test_votes.t fails with Firefox ESR 153 because go_to_bug doesn't wait for the module expand animation

qa/t/2_test_flags.t

@@ -328,8 +328,7 @@ $sel->title_like(qr/^$bug1_id /);
 # 1. going back does not keep panels expanded
 # 2. to get the requestee field to display for the addl flags,
 #    we have to set to X and then back to ? for each one.
-$sel->click_ok('action-menu-btn',   'Expand action menu');
-$sel->click_ok('action-expand-all', 'Expand all modal panels');
+expand_all_modules($sel);
 $sel->select_ok("flag_type-$flagtype1_id", "value=X");
 $sel->select_ok("flag_type-$flagtype1_id", "label=?");
 $sel->type_ok("requestee_type-$flagtype1_id", $config->{admin_user_login});

qa/t/4_test_user_privs.t

@@ -74,8 +74,7 @@ $sel->click_ok("log_in", undef, "Submit credentials");
 $sel->wait_for_page_to_load_ok(WAIT_TIME);
 $sel->title_like(qr/^$bug1_id/, "Display bug $bug1_id");
 $sel->click_ok('mode-btn-readonly', 'Click Edit Bug');
-$sel->click_ok('action-menu-btn',   'Expand action menu');
-$sel->click_ok('action-expand-all', 'Expand all modal panels');
+expand_all_modules($sel);
 
 # The assigned_to field must not exist.
 # But the 'Commit' button does exist.

qa/t/lib/QA/Util.pm

@@ -48,6 +48,7 @@ use base qw(Exporter);
   edit_bug_and_return
   get_config
   go_to_bug
+  expand_all_modules
   go_to_home
   go_to_admin
   edit_product
@@ -296,14 +297,37 @@ sub go_to_bug {
   $sel->title_like(qr/^$bug_id /, $bug_title);
   sleep(1); # FIXME: Sometimes we try to click edit bug before it is ready so wait a second
   $sel->click_ok('mode-btn-readonly', 'Click Edit Bug') if !$no_edit;
-  $sel->click_ok('action-menu-btn', 'Expand action menu');
-  $sel->click_ok('action-expand-all', 'Expand all modal panels');
+  expand_all_modules($sel);
 
   # Remove the blue New Changes link because the sticky banner causes a click interception issue in
   # Selenium that cannot be reproduced in real browser environments
   $sel->driver->execute_script('document.querySelector(\'.new-changes-link\')?.remove();');
 }
 
+# Expand all bug modal panels via the action menu and wait for the slide
+# animation to finish.
+sub expand_all_modules {
+  my ($sel) = @_;
+
+  $sel->click_ok('action-menu-btn',   'Expand action menu');
+  $sel->click_ok('action-expand-all', 'Expand all modal panels');
+
+  # Expanding uses a jQuery slide animation that sets overflow:hidden on the
+  # module content until it finishes. WebDriver treats the clipped fields as
+  # not displayed (get_text returns ''), so wait for the animation to end.
+  my $animating;
+  for (0 .. 50) {
+    $animating = $sel->driver->execute_script(
+      'return window.jQuery ? jQuery(":animated").length : 0');
+    last unless $animating;
+    select(undef, undef, undef, 0.1) if $_ < 50;
+  }
+  if ($animating) {
+    ok(0, 'Module expand animation finished within 5s');
+    diag("$animating element(s) still animating; later get_text calls may return ''");
+  }
+}
+
 # Go to admin.cgi.
 sub go_to_admin {
   my $sel = shift;