CORS Error oauth2

Hello !

I want to develop an application using the Blizzard API.

I wrote some code for the backend to use oauth2 blizzard authentication. After that I started the frontend. But when I tried to call the backend I got a cors error.

I wrote a stack overflow post with more informations.

I don’t know why and how solve my problems :cry:

Thank you for your help

The stack :

  • Spring boot for the backend
  • React for the frontend