Unable to log into GitHub in same Tab on Firefox

[fneu]

Hi, in our project we have a django backend running on port 8000 and an angular 4 frontend that used to be served from the same django instance, but is now being served on port 4200.

In Firefox we are now unable to authenticate with GitHub via social-app-django when visiting the respective address localhost:8000/auth/login/github in the current tab. Navigating to that address in a new tab or via window.open(...) works fine. In chrome this does not pose a problem.

We are unsure about the cause of this, but suspect it might be a problem in social-app-django.

Our specific issue is further discussed here in the repo of our backend. You can find the frontend in progress here.

We are using Django: 1.9 and Python: 3.6.1

Thanks in advance!