Ember Simple Auth state param

I'm using Ember Cli / EMber Simple Auth / Torii provider

In traditional Oauth2 flow I sometimes (mis)used the state param (GET) to have some stateful stuff survive the whole redirect business without having to resort to sessions, which I like to use as little as possible.

How would I go about doing this in ESA?

Use case: user hits login page from a link in an email, which appends some extra ?blabla=123. I want to send this blabla params to my backend along with the authCode.