Mozilla has not decided on a new platform for synchronous text communication. Hoyes reveals that there are several candidates that could replace IRC, and that candidates have to meet Mozilla's selection requirements:

Must be a product by another company or organization.
Self-hosted or pay for a service.
Needs to be accessible.
Needs to be a product, not a protocol.
Must be a proven, modern service.
Must support authentication because Mozilla Community Participation Guidelines will be enforced.

are you serious, fuck off