Since MV3 adds quite a lot of limits on what uBO can do, you have to grant permission for each site to have cosmetic filtering.
I wish people were not so quick to share misinformation like this.
For some reason people are just itching to spread FUD about this topic and Google in general. I don't understand where it comes from or why it happens but it's really annoying.
Edit: doesn't this mean that any site you visit will get a chance to track you the first time, until you manage to click to grant permission?