What is the expected response when we make request via Postman using url and base64 sources?

> Please provide us with the following information:
> ---------------------------------------------------------------

### This issue is for a: (mark with an `x`)
```
- [x] bug report -> please search issues before submitting
- [ ] feature request
- [x] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
> See screenshot below

### Any log messages given by the failure
> See screenshot below

### Expected/desired behavior
> Ideally, I'm expecting a response when a request is made to track the request sent.

### OS and Version?
> Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)

Windows 11

### Versions
> Python 3.11

### Mention any other details that might be useful
For urlSource works but what is it we need to do with it as there is nothing to track?

For base64Source I receive below error