Those extensions are from the same author. I don't know the details but maybe go...

pmontra 17 days ago | parent | context | favorite | on: Covert web-to-app tracking via localhost on Androi...

Those extensions are from the same author. I don't know the details but maybe gorhill didn't have the time to maintain uMatrix anymore and added the very minimum uMatrix functionality to uBO and settled for that. Luckily uMatrix keeps working.