Why "redirect_uri" is necessary in refresh token

[cnc0090306]

I've seen on the docs during Azure app registration, redirect_uri is optional here
https://docs.microsoft.com/en-us/graph/auth-register-app-v2?context=graph%2Fapi%2F1.0&view=graph-rest-1.0

So refresh token and get token does not require it as necessary, it is optional