Examine source code of Grey Orange Firefox

{
  "theme": {
    "images": {
      "theme_frame": "persona-perso2.png"
    },
    "colors": {
      "frame": "#d4c9c9",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Grey Orange Firefox",
  "manifest_version": 2,
  "description": "Simple Persona with the mention \"Firefox !\" for the lovers of FF"
}