Examine source code of Insta Media Downloader

{
  "manifest_version": 2,
  "version": "2.0.4",
  "name": "Insta Media Downloader",
  "description": "Download medias (every types) in a fast and easy way.",
  "author": "hawkynawa",
  "permissions": [
    "*://*.cdninstagram.com/*",
    "*://*.instagram.com/*",
    "cookies",
    "storage",
    "tabs",
    "activeTab",
    "downloads",
    "webRequest",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": [
      "js/utils/javascript.js",
      "js/utils/text.js",
      "js/utils/json.js",
      "js/utils/html.js",
      "js/classes/cmedia.js",
      "js/classes/cmedias.js",
      "js/classes/cidentity.js",
      "js/classes/cidentities.js",
      "js/imd_background.js"
    ]
  },
  "icons": {
    "16": "icons/imd_icon_16.png",
    "32": "icons/imd_icon_32.png",
    "48": "icons/imd_icon_48.png",
    "64": "icons/imd_icon_64.png",
    "128": "icons/imd_icon_128.png",
    "256": "icons/imd_icon_256.png"
  },
  "web_accessible_resources": [
    "css/imd.css",
    "icons/imd_icon_256.png",
    "icons/imd_icon_128.png",
    "icons/imd_icon_64.png",
    "icons/imd_icon_48.png",
    "icons/imd_icon_32.png",
    "icons/imd_icon_16.png",
    "icons/imd_dl_multi.svg",
    "icons/imd_dl_single.svg",
    "icons/imd_dl_single_white.svg",
    "js/utils/javascript.js",
    "js/utils/text.js",
    "js/utils/json.js",
    "js/utils/html.js",
    "js/classes/cmedia.js",
    "js/classes/cmedias.js",
    "js/classes/cidentity.js",
    "js/classes/cidentities.js",
    "js/imd_background.js",
    "js/imd_main.js"
  ],
  "content_scripts": [
    {
      "all_frames": true,
      "matches": [
        "*://*.instagram.com/*",
        "*://*.cdninstagram.com/*"
      ],
      "js": [
        "js/utils/javascript.js",
        "js/utils/text.js",
        "js/utils/json.js",
        "js/utils/html.js",
        "js/classes/cmedia.js",
        "js/classes/cmedias.js",
        "js/classes/cidentity.js",
        "js/classes/cidentities.js",
        "js/imd_main.js"
      ],
      "css": [
        "css/imd.css"
      ],
      "run_at": "document_start"
    }
  ],
  "options_ui": {
    "page": "settings/settings.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "hawkynawa@gmx.net_imd2"
    }
  }
}