Tesseract was a frontend for lemmy. Think of lemmy posts as emails, and the front end as your email client like outlook/gmail/etc. Normally you would expect your email client to show you your emails. But tesseract basically implemented a shadow ban list on users, communities, and phrases. And all of this was invisible to the server admins who hosted the tesseract frontend for their users. If you were banned by tesseract then people using that front ends just wouldn't see your post's, but you wouldn't show as banned in the tesseract UI. In the email example this is the equivalent of your gmail seeing you said "fuck ice" a year ago and now it'll let you send emails but not actually deliver them for people to read. But it wasn't just "fuck ice" it was a whole bunch of things like criticizing moderators, left and right wing ideas. And GirlsFrontline (anime style game) was banned but not porn. Just weird. And it did all of this by loading the ban list as obfuscated code at runtime so just zero transparency all around.

If someone wanted to make a less extreme lemmy then they could be open about their front end goals and not try to hide it like a punk ass bitch