Firebase SDK signInWithPopup() not working with Electron

I have an electron app that fires up a lightweight express server allowing me to use http in production for firebase github authentication.

I have this working fine using the signInWithRedirect() firebase auth method. However, i cannot get the signInWithPopup() method to work.

A new electron window launches, but the content is blank. Does my electron entry file need configuring for the above to work as expected?

This is working fine when i launch the app in a regular browser window which leads me to think electron needs configuring...