Element (the company from the Matrix.org core team) is super interested in providing refuge to Mozilla folks - we share the same goals of building the open web, albeit with a focus on open communication. (We'd put ourselves on the mozillalifeboat.com page, but I somehow doubt our Mozilla alumni uses FB... :D)
Particular areas that may be of interest include developer documentation (making https://matrix.org/docs/spec and https://github.com/matrix-org/matrix-doc not suck), Safety engineering (subjective decentralised reputation, anti-abuse and anti-spam), Rust (https://github.com/matrix-org/matrix-rust-sdk is in the ascendant), and even possibly VR (we are on a mission to ensure Matrix is the comms protocol of the multiverse) - although Safety & Spec (and generally hacking on Element and Matrix itself) are the most important domains right now. https://element.io/careers has more details.
Particular areas that may be of interest include developer documentation (making https://matrix.org/docs/spec and https://github.com/matrix-org/matrix-doc not suck), Safety engineering (subjective decentralised reputation, anti-abuse and anti-spam), Rust (https://github.com/matrix-org/matrix-rust-sdk is in the ascendant), and even possibly VR (we are on a mission to ensure Matrix is the comms protocol of the multiverse) - although Safety & Spec (and generally hacking on Element and Matrix itself) are the most important domains right now. https://element.io/careers has more details.