I understand how the Embed Kit allows us to embed a Figma Prototype within a webpage rendered inside a standard browser. The authentication is handled via Cookies within this browser (as far as my understanding goes).

I would like to embed Figma Prototypes that are not necessarily public in my mobile app using e.g. a WebView. In this case, I can not access the cookies from the standard browser. Is there a way (ideally similar to the REST API OAuth flow) to obtain a Figma session within my WebView so users can view their prototypes there? Are there other (secure) workarounds to allow my users to view their (nonpublic) prototypes within my WebView?