setCanonical example

        $this->eventDispatcher->dispatch(
            new NavigationPageLoadedEvent($page, $context, $request)
        );

        if ($page->getMetaInformation()) {
            $canonical = ($navigationId === $context->getSalesChannel()->getNavigationCategoryId())
                ? $this->seoUrlReplacer->generate('frontend.home.page')
                : $this->seoUrlReplacer->generate('frontend.navigation.page', ['navigationId' => $navigationId]);

            $page->getMetaInformation()->setCanonical($canonical);
        }

        return $page;
    }

    private function loadMetaData(CategoryEntity $category, NavigationPage $page, SalesChannelEntity $salesChannel): void
    {
        $metaInformation = $page->getMetaInformation();

        if ($metaInformation === null) {
            return;
        }