Auth0 Token Endpoint Authentication Method is faded out?

Question

I am suppose to change this field inside my client settings to something other than none, but it is greyed out and I cannot change it. Is there something else I have to do?

Answer 1

This will be intentionally greyed out if you have a Client Type of "Single Page Application" or "Native" as it does not make sense for those types. See below:

If your application were "Regular Web App" or "Non Interactive Client" this would become available.