"restart firefox" in readme

[kukosek]

i installed the theme then restarted firefox by closing and opening it. This didn't load the theme. I had to restart firefox with the button in about:profiles

[travisnewman]

It sounds likely that a Firefox process was still running somewhere. Any change you make to the css should just require a full restart, regardless of how you do it, BUT I suppose the button in about:profiles will make sure you close all processes.