Examine source code of Graphics Matter

{
  "theme": {
    "images": {
      "theme_frame": "browser-header.jpg"
    },
    "colors": {
      "frame": "#0067ab",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Graphics Matter",
  "manifest_version": 2,
  "description": "www.graphicsmatter.co.uk. design for print :: design for web"
}