TYPO3 Core

If a default page suffix like "/" is configured in the Site configuration.

This is caused by the folling process:

• The event listener TYPO3\CMS\Redirects\EventListener\AddPlainSlugReplacementSource generates a source by simply concatenating the base URL and the old slug slug, e.g. https://example.org/old-page-path
• After that, a second source is generated by TYPO3\CMS\Redirects\EventListener\AddPageTypeZeroSource. Inside this class, the source is generated with TYPO3's routing and respects the page suffix. This results in https://example.org/old-page-path/
• If both sources would be the same, the first one would be skipped. But because the are different, both are kept for further processing
• As last step, a redirect for each source is created, which leads to the result from the screenshot