What it bugs me is not that Mozilla pushed and extension into my/their browser but the behavior of the extension itself. It literally broke some pages, disrupting my use experience more than it was supposed to do (or at least I hope it was not intended). Peoples who complain about Mozilla pushing this just failed to check the basic browser options and should blame themselves instead. Anyway Mozilla seem to have rised quite a lot of attention about the secuirity and the privacy of their own browser with this stunt, so... it was a success, I guess?