Examine source code of Grey's Blue Gradient

{
  "name": "Grey's Blue Gradient",
  "manifest_version": 2,
  "version": "5.0",
  "theme": {
    "images": {
      "theme_frame": "FoxFire.png"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 1)",
      "tab_background_text": "rgba(224, 224, 224, 1)",
      "toolbar": "rgba(43, 42, 51, 1)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(28, 27, 34, 1)",
      "toolbar_field_text": "rgba(240, 240, 240, 1)",
      "tab_line": "rgba(98, 142, 204, 0.7)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a6307f1e-22c8-4c57-b560-d7604d7b3092}"
    }
  }
}