Windows client - nextcloud vs owncloud

My situation is that I need to sync files to two different servers. One is an ownCloud 10 server under my control, the other is out of my control and used be be owncloud, too, but was recently migrated to nextcloud 13.

Now my Windows desktop client (owncloud v 2.5.0) is issuing warnings that the connection to the Nextcloud server is not supported and to proceed at my own risk (which does not sound very reassuring for my files).

My question: Will this be the case in the future, too, or are there plans to align the clients to support both versions?

I would rather not have two clients running at the same time in order to support two different servers but I also don’t want to risk loss of data due to incompatibilities.

Or are there other clients that officially support owncloud and nextcloud?