Examine source code of Medieval Brick wall

{
  "theme": {
    "images": {
      "theme_frame": "Persona_Header_greybrickwall.jpg"
    },
    "colors": {
      "frame": "#474747",
      "tab_background_text": "#c4c4c4"
    }
  },
  "version": "2.0",
  "name": "Medieval Brick wall",
  "manifest_version": 2,
  "description": "A grey brick wall. Very simple but effective background with some nice shading."
}