How to force an OAuth error with Okta Sign In Widget

I’m using the Okta Sign In Widget and I was testing my custom LoginCallback with a failed challenge. It was failing (as expected) for a while when I had an invalid configuration (useClassicEngine set incorrectly) but now it won’t fail anymore.

Is there an way to force that initial challenge to fail so I can continue testing this failure path? I tried setting all of the fields to invalid values but I’m not able to generate an OAuth error again. Previously I was getting an invalid service provider.

Can you provide some context on your use-case? Are you unit testing the sign-in widget?

We have an application in the computer aided design area, wich is able to do REST calls either by basic authentication or by OAuth2 (especially for Google API).
One of our customer is using Okta for his services for single-sign-on and wants us to enable our application to work this.

So basically this small pyphon / flask application would help us a lot for testing.