A generic error message "Something was wrong" is raised when one clicks ok upon OAuth browser authentication.
The problem is due to new API version of Github (v3).
The error is the following: The server committed a protocol violation. Section=ResponseStatusLine
In the programming literature, there are some solutions for this error, but nothing seems to work.
Moreover, various C# wrappers for Github api have the same error message in the same line of code, using the HttpWebRequest C# object. All of these are now deprecated and is suggested to use oktokit for .NET 4.5
More in detail:
analyzing the packets in Wireshark, we can see that a good authentication to github api uses TLS protocol version 1.2; the bad one uses TLS v1.
In .NET 4 is not possible to use the v1.2, but only in the .NET 4.5