Examine source code of Tiger Wallpapers

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Tiger Wallpapers",
  "description": "Edit Firefox wallpaper with cute tigers",
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{359900b6-e70d-4c4a-a1ce-4f57ec0a977a}"
    }
  }
}