Examine source code of Shell Smart total points

{
  "manifest_version": 2,
  "name": "Shell Smart total points",
  "version": "1.1resigned1",
  "description": "Adds a total points of filtered transactions to transaction pages on shellsmart.com",
  "icons": {
    "48": "icons/shell-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.shellsmart.com/smart/account/transactions*"
      ],
      "js": [
        "jquery-3.1.1.min.js",
        "shell-smart-total-points.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{66295eba-b473-4d7a-aa67-2d08e55847ba}"
    }
  }
}