Examine source code of Russian Blue

{
  "theme": {
    "images": {
      "theme_frame": "untitled5.JPG"
    },
    "colors": {
      "frame": "#1c1b1a",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Russian Blue",
  "manifest_version": 2,
  "description": "Archangel Blue, Archangel Cat, Foreign Blue"
}