Join other enthusiasts in the Permanent Future Lab movement at the Permanent Future Lab Matrix chat space. Some locations have their own #channel.
With this decentralized free open source chat protocol you may decide which Matrix chat client you like to use. This is similar as with e-mail clients. FluffyChat is a popular and user friendly client which you can also use as web app directly from your browser. Other Matrix based clients will work as well. After installing a client or loading a web app you can register with an account. After registration you can join the space with an overview of groups by #permanentfuturelabspace:matrix.org
Before there were Discord and Slack chat which went less active. Since Matrix is fully Open Source and decentralized it was decided to move to Matrix.