Source
File: wp-includes/class-wp-hook.php
public function remove_filter( $tag, $function_to_remove, $priority ) {
$function_key = _wp_filter_build_unique_id( $tag, $function_to_remove, $priority );
$exists = isset( $this->callbacks[ $priority ][ $function_key ] );
if ( $exists ) {
unset( $this->callbacks[ $priority ][ $function_key ] );
if ( ! $this->callbacks[ $priority ] ) {
unset( $this->callbacks[ $priority ] );
if ( $this->nesting_level > 0 ) {
$this->resort_active_iterations();
}
}
}
return $exists;
}