Examine source code of Mouse King

{
  "theme": {
    "images": {
      "theme_frame": "Mouse-King.jpg"
    },
    "colors": {
      "frame": "#fad208",
      "tab_background_text": "#b5b5b5"
    }
  },
  "version": "2.0",
  "name": "Mouse King",
  "manifest_version": 2,
  "description": "The Mouse King"
}