Hi,
Thank you very much for the details, it helps a lot!
Sure! So the issue is casused by a long-url protection from the server side, where too much information is being sent because of the search filter states. The checkbox filter states have to be sent all at once and therefore it creates a too long URL. It rarely happens, only in cases when there is way too many options in a checkbox filter.
To resolve this, I have change the filters layout to a multiselect+search here for every filter box. It is very similar to the checkbox behavior, except the user can search and select the ones they want to filter by and also resolves the URI issue as much less information is sent to the results page via the long URL.
I hope this helps!