wie kann man Zugangsdaten & Passwörter exportieren oder drucken?

Here are some options:

Run code in Firefox's Browser Console

This will create a list either in the console (you can copy/paste) or in a new tab.

• CSV format: https://support.mozilla.org/questions/1253828
• JSON format: https://support.mozilla.org/questions/1077630#answer-834769

Use a third party program

I have not tested these myself:

• https://github.com/kspearrin/ff-password-exporter
• http://www.nirsoft.net/utils/passwordfox.html

Funktioniert leider nicht - Fehlermeldung: Problem reading or outputting logins: ReferenceError: Services is not defined debugger eval code:13:3

I'm sorry, I don't know why you are getting that error on your Firefox.

You are running the code in the Browser Console and not in the Web Console?

• https://developer.mozilla.org/en-US/Tools/Browser_Console