Scheduler settings entity dropdown selector broken in Claro

Hi jaydee1818,
Yes I can replicate this in 9.x (not tried in 10.x yet). It seems that the background for non-selectable menu items is transparent in Claro:

It is OK in Olivero as the background is solid:

For reference here's the same in Seven (although this is deprecated in drupal 9 now)

If anujasurve could not replicate it, maybe it is a browser-dependent problem? These shots were on Firefox 105.

FWIW I think Claro is an awful admin theme, far too much wasted space on the page requiring scrolling. Admin themes should be tight and efficient, it's not the front-end view. But that's not a reason not to try to fix this.

The dropdown is not doing anything tricksy. The non-selectable items just have a "title" attribute. Maybe there should be some extra attribute or class added for those?

      $links[] = ['title' => "-- $collection_label --"];
      foreach ($types as $id => $type) {
        $text = [];
        in_array($id, $publishing_enabled_types) ? $text[] = $this->t('publishing') : NULL;
        in_array($id, $unpublishing_enabled_types) ? $text[] = $this->t('unpublishing') : NULL;
        $links[] = [
          'title' => $type->label() . (!empty($text) ? ' (' . implode(', ', $text) . ')' : ''),
          // Example: the route 'entity.media_type.edit_form' with parameter
          // media_type={typeid} has url /admin/structure/media/manage/{typeid}.
          'url' => Url::fromRoute("entity.$bundle_id.edit_form", [$bundle_id => $type->id()]),
        ];
      }
    }
    $form['entity_type_links'] = [
      '#type' => 'dropbutton',
      '#links' => $links,
    ];

Other projects are also having difficulties with Claro
#3108997: [META] Claro theme UI improvements
#3174126: Improve layout when using claro
#3265668: Calendar with background color transparent when used with claro theme

Here's a patch for you to try. It solves it for me, but would be good to get others input.

We could raise a core issue to get Claro to add a default background, as contrib modules shoud not need to do this.

@jaydee1818 have you managed to test the fix yet?

I have raised #3317323: Claro dropbutton non-link items need solid background to get it fixed in Claro, but will also commit this to Scheduler as it could be ages before the core fix is done.

Fixed. Thanks again for reporting this.