Cannot query actual values “_blank” with underscore via graphql in Strapi

I create Enumeration values with underscore in Strapi, such as "_blank", "_self", and then query these values via graphql, the returned value is "blank", but if I query the value via RestApi, the returned value is "_blank".

create enumeration in Strapi

How can I query the actual value "_blank" via graphql in Strapi?