How can I approve external websites in the CSM agent KB?

[Jaime Capitel [Sngular]]

When configuring the CSM agent for a new customer experience, it's very easy to add articles from the connected Confluence instance.

However, I'm running in a bit of a loop when trying to add external websites.

I click under Knowledge in the Rovo Studio:

Then, I click on "Add knowledge" and land in this modal.

However, when I click on "Website", I inevitably land on this warning

I'm the org admin of this test site and the blue "Add" button does nothing. 

Does anybody know how to approve URLs here? Or is this a bug?