FHIR Service Base URL Test failing

I'm trying to complete Inferno Service Base URL test for FHIR endpoint and I thought it wanted host.com/fhir/r4/.well-known/smart-configuration but I get header error below. Am I using the wrong Service Base URL List or am I missing something? I'm running 2021.2 HealthShare

ERROR <HSFHIRErr>InvalidAcceptSpec: No valid Accept data found (Accept header or _format parameter)