Building sample app

I tried to do the getting started guide step by step. (Overwolf Basic Sample App · Overwolf)
So I could compile the app and I could load it as an unpacked extension, but if I press the load lunch button, nothing happens.
I’ve found in the logs the following error message: ContentVerifier - load content verifier error (MissingVerifiedContentsFile) Could not find a part of the path 'C:\Users\xxx\sample-app\_metadata\verified_contents.json'.
How can I generate that file? I didn’t found anything about that in the documentation

I’ve been working on an app for some weeks now.
Yesterday it was working fine.
Today, the app won’t load. I looked at the logs and they tell me the exact same error message as for you harald.
No clue why it happens now or how to fix it…

Edit: I found this:
Load content verifier error - Issues - Platform and API - Overwolf Developers Q&A