Examine source code of Gredos

{
  "theme": {
    "images": {
      "theme_frame": "skyline3.png"
    },
    "colors": {
      "frame": "#fc0808",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Gredos",
  "manifest_version": 2,
  "description": "Sky-line del circo de gredos invernal"
}