Examine source code of ANIMATED - Lightning City

{
  "theme": {
    "images": {
      "theme_frame": "LighteningCityscapeEdited.apng"
    },
    "colors": {
      "frame": "#030303",
      "tab_background_text": "#fcfcfc"
    }
  },
  "version": "2.0",
  "name": "ANIMATED - Lightning City",
  "manifest_version": 2,
  "description": "Animated lightning bolts light up the sky as soon you wear this theme. (You can't see\nthe animation in the preview but wearing the theme isn't permanent so you can try it. )\n\nCityscape made from: \n <a href=\"https://outgoing.prod.mozaws.net/v1/4476b17464be557d5a6e8a0f6eb09a7cefe4812f67d5e6e4efc8f5fa5cad5854/http%3A//www.flickr.com/photos/ttstam/2917556849/in/set-72157602215512676/\" rel=\"nofollow\">http://www.flickr.com/photos/ttstam/2917556849/in/set-72157602215512676/</a> #\n\nLightning photoshop brushes from obsidian dawn and starwalt design.\n(cartoon anime lightning bolts moving storm clouds night line lights scape metropolis colorful blue black tower high rise skyscraper dark)"
}