Examine source code of Catch a Scratch

{
  "name": "Pink Layers",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "abstrakt56.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(0, 0, 0, 0.62)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(250, 3, 65, 0.55)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{78d8777a-6e9b-4a19-9c40-3f7d015037fa}"
    }
  }
}