I've been using it for years and it's all good.

Pros:

self-hosted

Cons:

not easy to set up for beginners

Is it a fork of owncloud https://owncloud.org ??

One of the best open source projects of the decade. If you don't want to or cannot self host, /e/ foundation provides a hosted version which includes a free tier: https://e.foundation/ecloud/ If you're new to self hosting, Linode provides an easy one-click app and you can get the first couple of months free: https://www.linode.com/marketpla...

It combines lots of cloud features in one simple UI. And it can be self hosted..