Examine source code of Old Maps

{
  "theme": {
    "images": {
      "theme_frame": "OldMaps.jpg"
    },
    "colors": {
      "frame": "#855151",
      "tab_background_text": "#4f432d"
    }
  },
  "version": "2.0",
  "name": "Old Maps",
  "manifest_version": 2,
  "description": "Revolutionary maps"
}