This flow works correctly when we use the WDC through the Web Data Connector Simulator 2.0, which allows me to say that it is well implemented and there are no cross-domain issues.
However, when we do it in the Tableau internal browser, we see that the API requests reach the server without the Secure & HttpOnly cookie.
Has anyone come across this issue before? Is this a known issue of the Tableau internal browser? I wonder if the implementation of "fetch" in this browser is a bit aged and does not follow the latest standards?