@topher1kenobe Please use `absint` so that the check below can be updated to check whether mentioned post exists or not:

~~~php
$post_id     = absint( $data_mentionable->getAttribute( 'data-mentionable' ) );
$post_object = get_post( $post_id );

if ( $post_object )
	$mentioned_ids[ $id ] = true;

~~~