I don't know if it has anything to do with upgrading to J5.2.0 but the filter is not displaying correctly. See one filter in position header-search on this page, and another filter in position hero on the entry page.
meseko Hi
A weird issue, could I take a backup of your site and debug in my local environment?
saguaros Sure, can you get hold of files using FTP?
The issue here is that there is only 1 article in the filter but it's set to "Registered" level so nothing displayed.
I just tried to change it to Public and you can see the filter now.
Regards