When I install the Drupal 8 module and configure it, attempting to log in gives me this message: WE COULD NOT REACH THE SERVER. PLEASE CHECK YOUR CONNECTION AND TRY AGAIN.
Hi there @margyly, I apologize for the delay in response.
I understand it has been some time since you posted this question but I want to help if you are still facing this challenge or if someone else experiences it down the road.
If you are experiencing this when running local host through chrome, there was once an issue within the Chrome browser that would throw the No ‘Access-Control-Allow-Origin’ header is present on the requested resource but that has since been resolved.