You can find the first mention that Discover/Software would be replaced 3 months ago here.
It was also in our testing branches exactly as it shipped here for the last month. We would like it if more of our users participated in the testing branches.
Lastly we worked with multiple content creators to showcase Bazaar early on, Gardiner Bryant did a longform video on it over a month ago:
This is not something we’ll be exploring as our intent is to continue to grow and improve Bazaar and move away from legacy packaging. Ultimately if you want the old experience all I can recommend to you is spinning a custom image.
This is somewhat of a feature, Discover listed theme installers that are fundamentally incompatible with image based operating systems due to running arbitrary scripts that attempt to write to /usr. These had almost no moderation and were a possible security risk.
When running ujust update or the System Update app you’re always given a full list of changes before you reboot. You can also run ujust changelog at any time to see the latest GitHub release changelog, or follow along with our updates here in discourse.
User-friendliness. Even on SteamOS KDE flatseal is the application of choice for most users. It being present gives users a tool they’re likely already familiar with and it’s something Bazaar will be integrated with going forward.