@househippo,
I’m betting the URL limit issue was the result of trying to run the _doc_ids filter as a GET, as that could get really big.
I have looked at the client code, and I see where it’s dropping the filter params from the query string (the filter name gets placed in the query string in all cases, but the filter params get skipped for a POST). I think the right fix may be to set the request to a POST only if docIDs is set in ChangeTracker, but still do GET for all other filtered _changes queries. This way the query string doesn’t get out of hand due to large doc lists, and we’re still compatible with CouchDB. I’ll look into this change.
Thanks!