Error: You are not authorized to send a request through the cloud agent

I am unable to call any API endpoints or even a simple GET request to a web page using the Postman web interface.

When I try to make a request I receive the following error in the response window:
Cloud Agent Error: Unable to reach the Cloud Agent. Try later or select a different agent

And in the console:
Error: You are not authorized to send a request through the cloud agent

Full screenshot below (API key removed)

I am able to run the requests from the desktop client.

It is not specific to one API, I have tried multiple and also a simple GET request to google.com. I am not trying to connect to localhost, just publicly accessible APIs.

I also tried using the browser agent but then all requests result in a CORS error.

Is it possible to make requests via the Browser?