Doesn't work on latest version of OSX as of may25 2023, and Opera latest developer version.

[DioclesAI]

Installed it and set the browser spoof to blackberry, but when i visit https://www.whatsmybrowser.org
it clearly shows I am using Opera not blackberry

[z0ccc]

Works for me. Try reloading the page, it can take 1-2 page reloads when you first select a new user agent.