OAuth2 authentication and projections access failing

Thank you for the link. I finally found a solution in a blog from Damith Jinasena : https://dsj23.me/2021/01/08/ifs-authentication-flow-with-oauth-and-openid-connect/

Trying in my app using the details provided on this webpage did not work so I tried with his Sample app to demo OAuth2 from with PKCE in IFS 10 at the end of his blog: https://dsj23.me/2021/01/08/ifs-authentication-flow-with-oauth-and-openid-connect/#sample-app-to-demo-oauth2-flow-with-pkce-in-ifs-10

If that link above is broken, it opens this GitHub page: https://github.com/knakit/IFS-OAuth

That app was working with our own IFS instance but not with the IFS instance of our customer who was using ADFS as described in the link sent in the response of Ravi De Silva (I tried with the information in that page but same result: ok here but not working with our customer’s IFS).

Displaying a browser is required (as in solution from Damith Jinasena) but I realized that the corrent callback URL to use is not the one calculated by his sample app but is the one that Postman used (discovered after using Fiddler). I do not know how Postman calculate or find that URL but I put a patch in my code to use an alternate callback URL in the case of an OAuth2/ADFS connection.

I will mark the answer from Ravi De Silva as the Best Answer so that topic will be marked as solved.