Looking for a multi-user remote desktop system

Hi all! I'm looking for a remote desktop control system that works in Ubuntu. Something like VNC, but that allows for more than one user to remotely see and control the screen of this Ubuntu Desktop at the same time. I've been looking around for a while now, but all the solutions I've found only allow for one user at a given time. If a second user logs in, the first one is kicked out. I'm not sure if this is even possible, but I'd really appreciate any help pointing me in the right direction. Thanks!

Edit: What I'm looking for is something like https://tuple.app/, but open source.