How do I change the user agent reported by my Kindle Fire's browser? If I can't, is there a third-party browser for Fire that lets you do this?

I want to change it to reporting a Desktop or default user agent. All the instructions I can find on the web are outdated (they instruct you to change a preference the browser no longer seems to have – changing to “Desktop” view).

This is a recently-manufactured Fire running the latest OS.