Examine source code of Ksort

{
  "manifest_version": 2,
  "name": "Ksort",
  "description": "This extension will sort Kabum promos by discount",
  "version": "1.7resigned1",
  "permissions": [
    "activeTab",
    "http://kabum.com.br/",
    "https://kabum.com.br/",
    "http://www.kabum.com.br/",
    "https://www.kabum.com.br/"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": "icono.png",
    "default_title": "Sort Kabum Promos"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{560da18a-eeec-4342-9eef-47fbb5386d6c}"
    }
  }
}