The "attachment_icon" PHP filter in WordPress allows developers to modify the default icon displayed for file attachments. This can be useful for improving user experience and branding.

​The `after_signup_form` action in WordPress allows developers to execute custom code after the user has completed the sign-up process but before the footer is displayed

The 'atom_ns' action adds custom namespace declarations to Atom feed in WordPress.

The 'attachment_fields_to_edit' PHP filter in WordPress allows developers to customize the fields displayed on the media attachment edit screen. This filter can be used to add, remove, or modify fields…

The 'attachment_fields_to_save' PHP filter in WordPress allows developers to modify the fields saved when an attachment is updated.

Learn how to use the WordPress `admin_footer-{$GLOBALS[‘hook_suffix']}` PHP action to add custom content to specific admin pages, including examples and parameters explanation.

​The `admin_footer-{$hook_suffix}` action in WordPress allows developers to add custom scripts or data after the default footer scripts on admin pages by using the `$hook_suffix` parameter

The `admin_head_{$content_func}` action in WordPress is a dynamic action hook that allows developers to add custom code to the head section of the WordPress admin pages.

The 'admin_head-{$hook_suffix}' action in WordPress allows developers to customize the head section of admin pages with CSS or JavaScript.