There is a what's new link at the top of the post you linked. You can find it here though: What's New!
Additionally there is a release notes link just below the what's new link that would have additional details. You can find that link here: Release Notes
Was there something else beyond these that you were looking for?
Hey Dietmar! I should note that those are generalized links, and that you might be looking for more on the specific updates related to the release last week.
This release was a release in parallel with Veeam Backup and Replication patch 2 for v13.0.1 to keep things aligned. If you'd like to take a look at the things specifically fixed, you can find them here, but there is nothing specific to proxmox: https://www.veeam.com/kb4738