Firedragon is set up to use it’s own sync server (not Mozilla’s). If you want to set it up to use Mozilla’s sync server, that process is detailed elsewhere in the forum such as here: Firefox sync is not working with firedragon - #3 by BluishHumility
Are you sure you want to be using Firedragon in the first place? You can probably save yourself some grief by just using Firefox if you are just going to end up trying to defeat all the baked-in privacy features anyhow.