Examine source code of Christmas to Remember

{
  "name": "Christmas to Remember",
  "manifest_version": 2,
  "version": "5.0",
  "theme": {
    "images": {
      "theme_frame": "aCustom.jpg"
    },
    "colors": {
      "frame": "rgba(204, 9, 2, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(204, 16, 2, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(204, 16, 2, 0.07)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{67d5bcae-a54e-4955-9954-a7fab49bdba2}"
    }
  }
}