I have a page where I have a list of articles. In this list are published and unpublished articles. I ouput some data + the sefurl of each article.

Here's the problem: All links from sefurl of unpublishes articles have wrong sefurl which leads to a 404 error.

Sorry, I did not understand that. The Joomla button gets replaced by the articles anywhere plugin, isn't it? I posted the link to the frontend in my first post. It's about the wrong urls in the frontend:

I tested it with the core editor plugin. Same result, the links are broken. It doesn't matter if the article is trashed or unpublished, same behaviour. But what's really strange is the fact that it works for category 1 but not on category 2 (see demo). Also: for some unpublished items it does work and for some other not.

I tested it in a fresh Joomla 4 installation and I get different results. The URL is correct, but some parameters are incorrectly appended: https://www..domain.tld/page?view=article&id=333&catid=128 also resulting in a 404 error. I will ask in the forum, thank you.