Examine source code of Spooky Halloween

{
  "name": "Spooky Halloween",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Spooky Halloween.png"
    },
    "colors": {
      "frame": "rgba(149, 64, 165, 1)",
      "tab_background_text": "rgba(246, 140, 0, 1)",
      "toolbar": "rgba(246, 140, 0, 1)",
      "bookmark_text": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{04f360bb-463e-4020-b00b-46294194ec12}"
    }
  }
}