Our website is based on Nuxt.js and deployed to Netlify. Netlify domain is cuba-platform-en.netlify.app. We have a couple of services, which are served on the same domain with the static website. We configured redirects in Netlify to the subdomain, where our Nginx routes to those services.
Yesterday we changed the indentity provider behind the website. It is Keycloak which is hosted on an AWS cluster. Login is used to access the Discourse forum. Nginx routes to the forum.
If you click on the login button there is an error
Authorization timed out, or you have switched browsers. Please try again.
The error in console is CSRF detected.
However, the error is not always reproduced. Sometimes login works perfectly fine. Moreover, we tried the forum without Netlify with some rules in Nginx and etc/hosts custom mapping on a computer and it worked as well.
We have 3 other forums which work with the same instance of Keycloak. Netlify is not used on those domains. They work without any errors.
Do you have any ideas how Netlify can cause that error?