Angular FHIR Stackblitz authorization window refusing to connect

I am putting together a test app for connecting to FHIR in an angular application. It works great when running in VS Code and using localhost to run the app. I wanted to put it on stackblitz to assist anyone with the source code, however, when clicking authorize it refuses to connect to the endpoint. (appears in stackblitz browser window)

I do get a console warning when trying to authorize:

Your app is being authorized from within an iframe or popup window. Please be explicit and provide a "completeInTarget" option. Use "true" to complete the authorization in the same window, or "false" to try to complete it in the parent or the opener window. See

I added what the warning suggested and all it did was remove the warning, it still produces the same error within the window.

Here is the stackblitz to see the error. (click authorize button to see error)

The endpoint works in localhost as well as other endpoints, but in stackblitz they "refuse to connect". Any help would be appreciated. Comment if I need to provide more information.

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