And to make it worse, they started sending that tracking data through "functionality" endpoints to make it difficult or impossible for extensions like uBlock Origin to block without breaking the site. I believe it would pick a random endpoint out of a few possible choices, but as one example, it would sometimes use the same endpoint as voting, so that couldn't be blocked without also preventing you from being able to vote.

It's possible to detect the difference between the request types if you examine the actual data on them, but the common privacy extensions don't usually examine the requests on that level.