Examine source code of sunset_gradient_igd

{
  "name": "sunset",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "firefoxtheme.png"
    },
    "colors": {
      "frame": "rgba(255, 236, 204, 1)",
      "tab_background_text": "rgba(9, 87, 0, 1)",
      "toolbar": "rgba(255, 217, 242, 0.74)",
      "bookmark_text": "rgba(9, 87, 0, 1)",
      "toolbar_field": "rgba(247, 255, 248, 1)",
      "toolbar_field_text": "rgba(9, 87, 0, 1)",
      "tab_line": "rgba(173, 17, 116, 0.48)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e29baf35-0059-4ae4-ba91-e9a322baeb42}"
    }
  }
}