Examine source code of Betaserie Menu

{
  "manifest_version": 2,
  "name": "Betaserie Menu",
  "author": "Neicureuil",
  "version": "0.1",
  "description": "Add button for open betaserie in menubar (and not bookmark)",
  "icons": {
    "48": "icons/border-48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": {
      "16": "icons/page-16.png",
      "32": "icons/page-32.png"
    }
  }
}