Unfortunately, this extension doesn't actually block the link (at least not in the same way ad blockers do).

It just displays a pop-up window informing you that the page is blocked.
In devtools->network, I still see the page's traffic after the blocking message.

P.S. If this is helpful, the server can also be installed using the windows version of Python.
However, you need to add DATABASE_PATH = path to the .db database to your environment variables.