https://wccftech.com/gta-6-announcement-inside-gta-online-was-a-hoax-made-with-mods-rockstar-says/

The GTA 6 announcement that popped up over the weekend for some GTA Online players was a hoax, according to Rockstar Games.

An in-game message in GTA Online was teasing the arrival of the highly anticipated GTA sequel for some players over the weekend. We’ve included some screenshots showing the in-game message on various platforms below: