Examine source code of Contra-1

{
  "theme": {
    "images": {
      "theme_frame": "c-1.jpg"
    },
    "colors": {
      "frame": "#857b0d",
      "tab_background_text": "#a13914"
    }
  },
  "version": "2.0",
  "name": "Contra-1",
  "manifest_version": 2,
  "description": "The classic Contra game."
}