VersionError with Pouchdb and status 500 error. SOLVED

Got this "VersionError" message using Pouchdb. The solution was in the versions of Pouchdb. This sequence is important.

1. Replicated into the browser with Pouchdb version 3.1.0. This went well.
2. Then with version 3.2.1 of Pouchdb. No problem.
3. Finally went back to Pouchdb version 3.1.0. Got error of "VersionError".

I resolved the error by going back to version 3.2.1. 

The hint came from https://github.com/pouchdb/pouchdb/issues/2603 which talked about "because indexedDB itself can only bump the version up but not down."

Hope this helps someone.