Examine source code of FFBE Sync

{
  "background": {
    "persistent": true,
    "scripts": [
      "lib/jquery.min.js",
      "lib/core.js",
      "lib/md5.js",
      "lib/evpkdf.js",
      "lib/cipher-core.js",
      "lib/enc-base64.js",
      "lib/enc-utf16.js",
      "lib/format-hex.js",
      "lib/mode-ecb.js",
      "lib/aes.js",
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/iconeExtractor_32.png"
  },
  "description": "Download your FFBE data to file to be able to import it in FFBE Equip",
  "icons": {
    "16": "icons/iconeExtractor_16.png",
    "32": "icons/iconeExtractor_32.png",
    "48": "icons/iconeExtractor_48.png",
    "128": "icons/iconeExtractor_128.png"
  },
  "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEApMPWtk6eX0Dd+H6fAoDoCUAnMhFJQdivhhAIK95VVeDosflMuOrHUWjWc0xU1T1iIsWrxA2xyfnuKQWzFWJSLVtkfPFGMpkjqOYyafyqITlEGEF7wxV0anpF0ZMImnVDZ4kdVHNir9t9Dp2bSkzTm8/sdk4sfI2yz4zJLhor1uWFbSBlOwaleo1GUtdkXAx5j2wljdDyUp0sZtDDTF7M3UJupeXaNDKkEFoLeJ55FujM2+lhDfoD02NqM9RMpp5vKrrPFCkjVSajLgpsPZzKTP+eNbu4KuPaNa0lwvVQwb+07b861R3JpILPg6SeBG9ui9lC+FaAQ+TbXVyRhbIt0QIDAQAB",
  "manifest_version": 2,
  "name": "FFBE Sync",
  "permissions": [
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "https://*.facebook.com/*",
    "https://lapis340v-gndgr.gumi.sg/*",
    "https://android.googleapis.com/auth",
    "https://accounts.google.com/*"
  ],
  "web_accessible_resources": [
    "ffbeSync.html",
    "ffbeSync.js"
  ],
  "update_url": "https://clients2.google.com/service/update2/crx",
  "version": "2.5.15",
  "browser_specific_settings": {
    "gecko": {
      "id": "{5d13c6a3-8d39-4f8a-8abf-3a73d2ba96a1}"
    }
  }
}