Webmin repo missing updates

The updates you're seeing are development releases. We sometimes roll those into the Virtualmin repo in order to quickly address specific bugs that effect Virtualmin users, or to prepare for a new version of Virtualmin that requires new Webmin features that aren't in the stable release of Webmin yet.

There's nothing wrong with the Webmin repos. They just only get minor version releases when there are security bugs or major bugs that effect a lot of users. You can find the development releases on the Webmin page under the Development Versions link. You could also use the Virtualmin repos for your Webmin packages...but, Virtualmin sometimes trails the Webmin repos when there's something that prevents us from rolling forward (or just because I haven't had time to test and roll it out).

Anyway, the 1.844 release has fixes specifically for the new Virtualmin 6 release that's in development, as well as some changes for Authentic theme new releases. If you aren't running into the specific problems the release was made to fix, you probably don't need to worry about it. There will be a new stable Webmin release soon.