Hi Patrick,
Greetings from Syncfusion support
We have validated your query “After L10.load German Locale = Cannot convert undefined or null to object”
The reported issue will got occurred, when the CLDR-data for the corresponding culture is not loaded in the application. So, please ensure that whether the culture file for the corresponding culture is correctly loaded in your application. Also, ensure that whether you have referred the CLDR data from the node_modules correctly. Please check the below link for further details,
Please check the above sample and documentation and let us know if it resolves your issue.
Regards,
Vinitha.