I accidentally deleted the repo the original PR was based upon haha. 

Anyway, the code was still on my computer so here's a new PR with the same content. 

I addressed the latest comments from @lfades in the old PR (https://github.com/vercel/next.js/pull/14180)

I also updated `next-auth` to `2.1.0` and updated the `<Provider />` component in `_app.js` that needed updating since the latest release.

Let me know if I missed anything else, otherwise I think this should be good to go 👍