Query demands required parameter after version update

[QnavWhat]

Hi, I just updated from Version 6.3.0 to 6.6.0 and without changing the queries, I get the following error message when running GraphQL calls:

{"(400 Bad Request) query: Required parameter missing or invalid"}

The same query runs fine with the previous version and I could find any change log with related information. The higher versions I tested return this message as well. I get the error message for every query I tested like ''query MyQuery { shop { name } }". When using e.g. POSTMAN I can run the query without exception.

Thanks and regards