Using WordPress ‘comment_{$new_status}_{$comment->comment_type}’ PHP action
The 'comment_{$new_status}_{$comment->comment_type}' PHP action is a WordPress hook that is triggered when the status of a comment is changed.
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Using WordPress ‘comment_notification_headers’ PHP filter
The 'comment_notification_headers' PHP filter in WordPress allows developers to customize email headers for comment notifications.
Using WordPress ‘comments_atom_head’ PHP action
The `comments_atom_head` WordPress action allows you to modify the Atom comment feed header by adding custom content, changing the generator tag, or adding custom meta information
Using WordPress ‘dbx_post_sidebar’ PHP action
The `dbx_post_sidebar` WordPress PHP action is used to fire after all meta box sections are outputted on a post page, before the closing `#post-body` div element