Synchronising Firefox with Apple Passwords app.

Hi all. I suppose this applies as much to Firefox on the desktop as it does to iOS, really. I'm having real trouble with passwords, now that I've moved over from Safari to Firefox & Apple have seen fit to create a standalone Passwords app. (Life was so much simpler before they did that!) I have the extension installed, but I'm getting mis-matches between the two (or three if you count the phone, meaning: Passwords App, Firefox Desktop & Firefox iOS). I suppose the way it should work in my head is that when Firefox asks me if I want to save a password, it should save it to the passwords app (although I have no problem if it saves the password into the Firefox preferences too) & when I go to log in somewhere, it should call the password from the passwords app, but it doesn't seem to be doing that, I'm just getting multiple versions of log-ins everywhere. I just had to reset my Instagram log-in. Firefox generated the password & it's now saved in the Firefox passwords list but it hasn't appeared in the Passwords app. Shouldn't the extension be keeping them synchronised?