How to login in Skype via Facebook? I have a skype account that I created via Facebook login and can use it on my PC or Mac just fine. Now I want to use Skype on Android and have installed the official app. Yet the app lacks an option to login via Facebook.

How am I supposed to login, as I do neither know my user name nor the password, as I am used to login via Facebook.
Go to the login page, tap on "Problems in signing".
Enter your primary Facebook email, Skype will send a code to your email.
Copy it, go back to the Skype app. 
Tap on enter the key, paste the key in it.
There's your Skype account named facebook:your.name.
Tap on your Facebook profile, tap sign in with Facebook
Then Facebook login page will appear and enter your login info.