Choosing From All The Tags When Editing A Post

    

add_filter( 'get_terms_args', 'themeprefix_show_tags' );
 // Show Tags
 function themeprefix_show_tags ( $args ) {
 if ( defined( 'DOING_AJAX' ) && DOING_AJAX && isset( $_POST['action'] ) && $_POST['action'] === 'get-tagcloud' ) {
 unset( $args['number'] );
 $args['hide_empty'] = 0;
 }
 return $args;
 }