I am building a web app where all server requests are handled through AWS Gateway and Lambda. I have introduced AWS Cognito for sign-up and sign-in which works very well.
I am planning now to activate Facebook sign-up and sign-in. However, from what I understood, Facebook redirects to user after successful sign-up/in. Given that I dont really have a backend server, I was wondering whether there is an option to get the FB access token in my Javascript code without redirecting/refreshing my site?