So, in case anyone ever gets this problem as well, here’s more or less what happened:
on the server in a subfolder, there was still another MODx install, which I used for building and testing the site. After I finished building I copied the site to the root, but didn’t delete this subfolder. It looks like the chunk from the test site was used in some pages instead of the modified chunk in the root install.
I probably forgot to edit an .htaccess file somewhere and never noticed this, because everything else was still working ok. Oh well, everything’s fine now
and I apologize for wasting people’s time
