I am using Drupal Lightning 8.x.2.2.3. And I am using the the built in Lightning Embed button (the one with the Star icon) added to the Ckeditor to add media to the body. The Embed button is using the Media Browser. On the Embed button settings page here: /admin/config/content/embed/button/manage/media_browser?destination=/admin/config/content/embed. There is a filter to restrict by Media Type. It says If none are selected, all are allowed. This option does not restrict anything, is this a bug? I have the Document Type checked and it still allows Images when I go to upload media. Example when I click one the Embed button in the Ckeditor. And then I click on tab Upload. The widget 'file upload' is being used. And I can upload images. Can a custom hook be created to restrict file types through the File Upload widget? I know you can further restrict file types here: /admin/structure/media/manage/image/fields/. But I need to restrict it up further at the browser on button level. The other widget called 'Upload images as media items' has a setting to restrict by file types. But it uses a different form ID then File Upload widget. The 2 widget work Differently.