GET requests for the current configuration of blueprint modules don't work with default configuration.
But it starts to work when the default configuration has been changed (e.g. by RESTCONF PUT request).
Example of blueprint XML and Yang model attached.

Example of the GET reqest URL and response body:

GET: localhost:8181/restconf/config/onem2m-plugin-loader-config:onem2m-plugin-loader-config

{
"errors": {
"error": [

{ "error-type": "application", "error-tag": "data-missing", "error-message": "Request could not be completed because the relevant data model content does not exist " }

]
}
}