Examine source code of Daily Thoughts Emotes

{
  "manifest_version": 2,
  "name": "Daily Thoughts Emotes",
  "version": "1.0",
  "description": "Remplace les emotes dans les mails Daily Thougts par leur image prise sur 7tv",
  "icons": {
    "48": "icons/icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://partage.insa-cvl.fr/*"
      ],
      "js": [
        "app.js"
      ]
    }
  ],
  "permissions": [
    "*://7tv.app/*",
    "*://betterttv.com/*",
    "*://partage.insa-cvl.fr/*",
    "*://api.frankerfacez.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f85e6283-f939-45e3-a3cc-c48d328f91a0}"
    }
  }
}