uMatrix's privacy policy:

uMatrix does not collect any data of any kind.

• uMatrix has no home server.
• uMatrix doesn't embed any kind of analytic hooks in its code.

The only time uMatrix connects to a remote server is to update the hosts files and other related assets. If you disable auto-update in the "Hosts files" pane in the dashboard, uMatrix will not connect to any remote server, unless you click "Update now" and only if there are assets deemed "out of date".

The project is currently hosted on github.com, which is owned by GitHub, Inc., and thus is unrelated to uMatrix.

That is all.