Lemmy

Thanks to Marius, looks like when you interact with a server you get assigned a local id that's tied to your username/email combo. So no global ID but all your actions on a server are tied to you. It wouldn't take a lot to link that to your account on your home server.

Overall idk if it's a big deal. Upvotes and such need to have a user ID tied to them in order to keep things straight. Unless someone wants to update the Lemmy software to start encrypting the GUID on the table an instance owner will always be able to see what you've voted on ON THEIR instance. Reddit totally can as well, but they had a reason not to put their users on blast (At least until lately lol).

It'd take some collusion to put that all together across the fediverse.

The table that store upvote is named comment_like and post_like. Here, you have the vote’s unique id, the local user id that is linked to the it’s "global id", the local post id which is also linked to it’s "global id", the value of the vote (+/-1) and the date.

So votes are indeed totally not anonymous.

(and I run my server sinces less than a week, and the sum of entry in the two table is of 114 950 votes. Certainly enought for doing a bunch of analysis.)

Example of datas for the comment vote table (ids has been changed)

  id   | person_id | comment_id | post_id | score |         published          
-------+-----------+------------+---------+-------+----------------------------
     1 |        10 |          3 |      61 |     1 | 2023-06-17 20:01:20.948684
     2 |        34 |          1 |      22 |     1 | 2023-06-17 20:01:26.346783
     3 |        12 |          2 |      54 |     1 | 2023-06-17 20:01:27.627144
     4 |        20 |          7 |      91 |     1 | 2023-06-17 20:01:36.570636

Ping @[email protected]

Kbin shows all votes and I’m pretty sure I saw my lemmy.world account upvote show in the “activity” of a post on kbin.social.

I may be mistaken, though. I have an account there, too. It’s very possible that I was looking at my own vote from my own local kbin account.

Is that ID local to the instance or universal across the fediverse?

I dunno, this is as far as I chased it. It should give you a starting point to dig further if you choose... but I don't plan to at the moment.

As far as I know (another assumption haha), there’s no universal IDs across the fediverse.