They do that distinction, the only confusion here is that they also include language that allows them to act as the User Agent. That's everything that pertains

They do that distinction, the only confusion here is that they also include language that allows them to act as the User Agent. That's everything that pertains to Firefox the browser. Everything else is about services that are available through Firefox the browser: Sync, Pocket, New Tab, Telemetry, Studies, etc.