In test1 web site I can get debugging information with a Post link

In test2 web site, running the same api, I cannot. I just see
Failed to load resource: the server responded with a status of 500()
In test1 web site I can get debugging information with a Post link

In test2 web site, running the same api, I cannot. I just see
Failed to load resource: the server responded with a status of 500()
In web.config
<httpErrors errorMode="DetailedLocalOnly" existingResponse="Auto" />