CheckoutFinishPageLoadedHook example

return $this->redirectToRoute('frontend.checkout.register.page');
        }

        try {
            $page = $this->finishPageLoader->load($request, $context);
        } catch (OrderException $exception) {
            $this->addFlash(self::DANGER, $this->trans('error.' . $exception->getErrorCode()));

            return $this->redirectToRoute('frontend.checkout.cart.page');
        }

        $this->hook(new CheckoutFinishPageLoadedHook($page, $context));

        if ($page->isPaymentFailed() === true) {
            return $this->redirectToRoute(
                'frontend.account.edit-order.page',
                [
                    'orderId' => $request->get('orderId'),
                    'error-code' => 'CHECKOUT__UNKNOWN_ERROR',
                ]
            );
        }