Could you describe what your desired outcome is? What is it that you are trying to achieve? Are you trying to get a viewer’s Twitch ID?
If so, see Extensions Reference | Twitch Developers
If you are trying to leverage some other authenticated Twitch functionality, I would suggest reading the content policy for Extensions first: Extensions | Twitch Developers
In particular:
Extensions may not request or require OAuth permissions from extension viewers.
I am not sure whether I have answered your question, as I am not too sure what it is. 