ext_localconf.php

<?php

$GLOBALS['TYPO3_CONF_VARS']['SYS']['routing']['enhancers']['ExtbaseRequiringPluginOnPage'] = 
  \Lemming\SiteExtension\Routing\ExtbaseEnhancerRequiringPluginOnPage::class;

ExtbaseEnhancerRequiringPluginOnPage.php

<?php

namespace Lemming\SiteExtension\Routing;

use TYPO3\CMS\Core\Cache\CacheManager;
use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Database\Query\QueryBuilder;
use TYPO3\CMS\Core\Routing\RouteCollection;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Extbase\Routing\ExtbasePluginEnhancer;

/**
 * Records across multiple tables may have the same slug. An event record may not be shown when the earlier enhancer for news
 * finds a news record having the same slug.
 *
 * We don't want to use the routing feature "limitToPages" with a static list of page ids.
 *
 * With this enhancer we check if there is a plugin on the page for the wanted record type. If not, this enhancer
 * does nothing.
 */
class ExtbaseEnhancerRequiringPluginOnPage extends ExtbasePluginEnhancer
{
    public function enhanceForMatching(RouteCollection $collection): void
    {
        if (!$this->isRoutePathFullyDecorated($collection) && $this->isPluginOnPage($collection)) {
            parent::enhanceForMatching($collection);
        }
    }

    /**
     * Check if there is something to decorate. Given url path = page slug then nothing needs to be enhanced.
     *
     * This is called for
     *   - /anypath/news/news-title
     *   - /anypath/
     *   - /
     *
     * and only the first is interesting so we can cache the result.
     */
    protected function isRoutePathFullyDecorated(RouteCollection $collection): bool
    {
        $runtimeCache = GeneralUtility::makeInstance(CacheManager::class)->getCache('runtime');
        if ($runtimeCache->get('skipExtbaseEnhancerRequiringPluginOnPage')) {
            return true;
        }

        $options = $collection->get('default')->getOptions();
        $isRoutePathFullyDecorated = isset($options['_decoratedRoutePath']) && $options['_page']['slug'] === $options['_decoratedRoutePath'];
        $runtimeCache->set('skipExtbaseEnhancerRequiringPluginOnPage', true);
        return $isRoutePathFullyDecorated;
    }

    protected function isPluginOnPage(RouteCollection $collection): bool
    {
        $listType = strtolower(implode(
            '_',
            [
                $this->configuration['extension'],
                $this->configuration['plugin'],
            ]
        ));

        $options = $collection->get('default')->getOptions();
        $pageUid = $options['_page']['l10n_parent'] > 0 ? $options['_page']['l10n_parent'] : $options['_page']['uid'];

        /** @var QueryBuilder $queryBuilder */
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('tt_content');
        $count = $queryBuilder
            ->count('*')
            ->from('tt_content')
            ->where(
                $queryBuilder->expr()->eq('pid', $queryBuilder->createNamedParameter($pageUid, \PDO::PARAM_INT)),
                $queryBuilder->expr()->eq('list_type', $queryBuilder->createNamedParameter($listType))
            )
            ->execute()
            ->fetchOne();

        return (bool)$count;
    }
}