ueued processors and whether they are scheduled or not to
	 * either re-eschedule them or remove them from the queue.
	 * This prevents stale states where Action Scheduler won't schedule any more attempts but we still report the
	 * processor as enqueued.
	 *
	 * @since 9.1.0
	 */
	private function remove_or_retry_failed_processors(): void {
		if ( ! did_action( 'wp_loaded' ) ) {
			return;
		}

		$last_error = error_get_last();
		if ( ! is_null( $last_error ) && in_array( $last_error['type'], array( E_ERROR, E_PARSE, E_CORE_ERROR, E_COMPILE_ERROR, E_USER_ERROR, E_RECOVERABLE_ERROR ), true ) ) {
			return;
		}

		// The most efficient way to check for an existing action is to use `as_has_scheduled_action`, but in unusual
		// cases where another plugin has loaded a very old version of Action Scheduler, it may not be available to us.
		$has_scheduled_action = function_exists( 'as_has_scheduled_action') ? 'as_has_scheduled_action' : 'as_next_scheduled_action';

		if ( call_user_func( $has_scheduled_action, self::WATCHDOG_ACTION_NAME ) ) {
			return;
		}

		$enqueued_processors    = $this->get_enqueued_processors();
		$unscheduled_processors = array_diff( $enqueued_processors, array_filter( $enqueued_processors, array( $this, 'is_scheduled' ) ) );

		foreach ( $unscheduled_processors as $processor ) {
			try {
				$instance = $this->get_processor_instance( $processor );
			} catch ( \Exception $e ) {
				continue;
			}

			$exception = new \Exception( 'Processor is enqueued but not scheduled. Background job was probably killed or marked as failed. Reattempting execution.' );
			$this->update_processor_state( $instance, 0, $exception );
			$this->log_error( $exception, $instance, array() );

			if ( $this->is_consistently_failing( $instance ) ) {
				$this->log_consistent_failure( $instance, $this->get_process_details( $instance ) );
				$this->remove_processor( $processor );
			} else {
				$this->schedule_batch_processing( $processor, true );
			}
		}
	}
}