In part this is because Sumatra 0.7.4 was stable, and seemed to meet the needs of its users, in part it is because I was working on other projects, in which I wasn't using it. I now have time again to work on Sumatra, and I am starting some new projects for which I will be actively using it, so I decided to update it, merge as many of the outstanding pull requests as I could, and make a new release.
The new release requires Python 3.9 or later, and Django v4 or v5. For a more complete changelog, see https://sumatra.readthedocs.io/en/latest/releases/0.8.0.html.
I don't know how many members of this mailing list are still using Sumatra. If you are, please let us know by posting a reply! If you've stopped using it because it was too hard to install given the outdated dependencies, please give it a try once more. And if you've stopped using it for some other reason, for example because you've found a better solution for tracking your projects, please also let us know.
Andrew