Once again daddy Google being an absolute asshole against projects that can damage their tracking practices.
Meanwhile you can download the extension from their GitHub or use Tracking Token Stripper if you need to use Chromium-based browsers, or. you know… just use Firefox.
uBlock is too widespread and well-known at this point, they do this to smaller projects because they can and they know that it won’t cause as much of a pushback from the general public.