Hello,
i am currently using Nextcloud Hub 8 (29.0.4), using Docker Desktop on Windows. I have searched Youtube, the GitHub repo and of course the forums, but I can’t figure out how to update Nextcloud using Docker Desktop. Is there any guide for Docker beginners or maybe someone who can share the exact steps on how to update Nextcloud using Docker Desktop? I am absolutely lost (and by this point quite annoyed by docker -_-, why does it have to be that complicated?).
Thank you 
Hello and welcome to the forum.
Is your question related to a migration from NC 29 to NC 30 or just an update within the NC29 branch?
Generally, you should learn the principles of docker: You have images (think of stamps) that you can use to create marks on paper (containers). You can now work with the papers as you like. If you want to upgrade, you have to update the stamp.
In docker, you can do the fetching of the (new) images by means of docker pull. Docker Desktop should have the corresponding feature to pull the corresponding image from the docker hub. You did not write which docker image you are using, thus I cannot give you a clear statement on what image label you need to look.
After that, you need to recreate the container. Attention: Nextcloud does not allow downgrading (29 → 28) and not allow to skip a major release (28 → 30). Recreate the container and the server will trigger an upgrade process.
Christian