Examine source code of Rulemar

{
  "name": "Rulemar",
  "description": "Lista de precios, catalogo y stock.",
  "version": "1.2resigned1",
  "icons": {
    "128": "logo.png"
  },
  "browser_action": {
    "default_icon": "logo.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs"
  ],
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "{e57523f3-c252-49d7-a7f2-1e21bf31b683}"
    }
  }
}