How to Generate an App Password on Facebook
Some Facebook applications don’t work with Facebook login approval codes, so if you have that option enabled, you may not be able to use all your apps. Facebook has fixed it so you can use app passwords instead of your account password to log in to certain apps (for example, Skype).
According to Facebook’s Help section, when you use an app password you won’t have to wait to receive a [login approval] code. Instead, you can skip login approvals and log in immediately. Check here to read more about app passwords.
To generate an app password, follow these instructions:
In the App Passwords row, click Edit.
Click the Generate App Passwords link.
The Generate App Passwords dialog box appears and explains that some apps don’t work with login approvals.
Click the Generate App Passwords button.
In the text box, type the name of the app you want to approve and then click Generate Password.
A window appears, with the choice of creating another password (click Next Password) or finishing (click Finish).
To complete the process, click Finish.
If you want to create another password instead, click Next Password and repeat Step 4.
You can remove a password by clicking App Passwords and then clicking the Remove link next to the password you want to delete.