Examine source code of Uptodown

{
  "theme": {
    "images": {
      "theme_frame": "headerperson3.jpg"
    },
    "colors": {
      "frame": "#072182",
      "tab_background_text": "#072182"
    }
  },
  "version": "2.0",
  "name": "Uptodown",
  "manifest_version": 2,
  "description": "Uptodown.com skin"
}