How to pass user's language selection to React application

[mathiasconradt]

This question came up a few times in the forum:

How to pass custom parameter to a custom OAuth2 connection?

As mentioned in the comments, the additional parameters that can be sent need to be recognized by the receiving endpoint which is mostly expecting OpenID Connect/OAuth2 standards parameters or some custom parameters already being used by popular providers. For example, this would be the case for the access_type parameter mentioned in the docs. Despite this requirement custom OAuth2 connections can be configured to automatically map a known and accepted parameter, like the access_type one, to a …

https://community.auth0.com/t/passing-additional-inputs-from-universal-login-page/39581/8?u=mathiasconradt

Another option, in case it’s not mentioned in the linked questions, to use different callback urls, something like https://callback/?lang=de and https://callback/?lang=en