IMO the real revolution might be a decision to integrate notmuch so to move from a '90s-like UI/workflow to a modern era one so powerful that can easily outshin

IMO the real revolution might be a decision to integrate notmuch so to move from a '90s-like UI/workflow to a modern era one so powerful that can easily outshine webmails. Also, with a proper maildir cloning support (mbsync like for instance) it may give to the casual users the opportunity to have locally their messages. Otherwise anything Mozilla can do can at maximum keep a zombie alive simply because of lack of less ugly widespread and generic alternatives.