Nextcloud update 20.0.8 -> 20.0.9: Exception: Updates between multiple major versions and downgrades are unsupported

[Mornsgrans]

I did it two years ago as described here:

How to dismiss Nextcloud update message in UCS software update?

I got it! I cannot grant, that the described method will work for everybody. - Do a full backup, before you try to follow the steps below. Today I spent some time to look, how to get rid of the message mentioned in my first posting. As mentioned in my first posting I did install Nextcloud 15 together with my UCS. From time to time I got a message after logging in with my Firefox, that a new Nextcloud version was available. So I installed it every time. The latest version was 17.0.3. last Fe…