I'm on the Desktop Spotify. I click 'Log in with Facebook', it opens up Firefox, says 'logging in' and then 'you may now close this window', but it doesn't actually log in on the desktop app. I am logged in through Facebook on the website, but the two aren't connecting.
@rivs89, I am receiving a similar problem but instead, when I click "log in with Facebook", a new tab opens in my browser and all I see is "Logging in to Spotify" and it never resolves. I'm using Internet Explorer 10