How does Reddit track users?

Question

Experimenting with multiple accounts, I've found that they're able to track devices even when I use TOR browser and follow the instructions (no plugins, not maximizing windows, etc.) With an account already banned, I can create as many new ones as I like, but they are shadow-banned from the start and posts aren't ever visible to anyone else.Apart from the usual data (OS, CPU, GPU), what other information do they collect that makes it possible for them to match new users with existing ones? Are there any simple ways to prevent this fingerprinting?

MattGaiser · Accepted Answer

Pretty much all Tor accounts are shadowbanned from the start. It is pretty common for Tor IPs to just be banned from the start on sites given the volume of abuse.
Reddit also uses cookies to track together your accounts together when not using Tor. My friend got to the point where any account she tried to use was shadow locked out, i.e. as soon as you tried to log in on the poisoned browser, it locked the account and any account that followed. Clearing the cookies solved that problem.
They also appear to have some kind of language profiling for certain topics and new accounts.
Source: Lessons from a friend working at a company that heavily relied on spamming Reddit for customers. A heck of a lot of creative things were tried to continue that.

detaro · Answer

Presumably they don't link your Tor accounts to your old one, but just ban all accounts created through Tor.

readflaggedcomm · Answer

You can test your tracking assumption: boot into TailsOS, maybe connect over a different ISP or VPN. The other comments are correct. They're blocking Tor, not just you.