[Feature request] Descriptive details for Authorization flow errors

[symdeb]

Is your feature request related to a problem? Please describe.
I have an OAauth authenication service on a localhost and on an external hosted site returning the same token json but the one on the external server fails while the one on localhost passes.
For example The token request failed and the error is
Error: Failed to fetch

Describe the solution you'd like
A more detailed for the reason for the failure. A header issue ? A content issue ? A format issue ?

Describe alternatives you've considered
Trial and error, changing response headers ..etc..

Additional context
Error messages without details waste a lot of time trying to identify the root cause

[leoporoli]

+1