Hey Alexander,
the lazy loader is Loader Script for Browser JavaScript | Sentry Documentation
The script url itself is accessible via Settings > Projects > [javascript project] > Client Keys (DSN) > Configure > Javascript Loader
As for the reproduction, I’m not quite sure, I’ve followed the normal setup, run the install.sh script and docker-compose up. After adding the script in my project and throwing a test error in the client code, I get the aforementioned message from the script
The Sentry loader you are trying to use isn’t working anymore, check your configuration.