Take a look at the parameter list for the refresh access token call:
It clearly states refreshing a token has no optional params, and lists
- redirect_uri <---- can be omitted and with successful result
as required. But even so, omitting the redirect_uri body param, or just sending it with no value still successfully refreshes the token!
From a logical perspective this makes sense to me, why would i need the redirect_uri param after the first token has been successfully acquired, but I would like to know if this is a documentation error or if it indeed is an optional parameter?