Help about:debug problems

[MadOmega]

I wanted to view a site on my Desire, that kept redirecting me to it's mobile version, and I read that if I type about:debug in my browser I can change Android to desktop in user agent.
Now I tried to type it without http and it does not show me no options or anything and if I leave http it said web page not available.
Any hints on what I'm doing wrong or what I need to do?

 

[MadOmega]

Managed to understand, about:debug did visibly but gave me more options in menu>more>settings.