Examine source code of Launch Gmail

{
  "description": "Gmail toolbar button",
  "manifest_version": 2,
  "name": "Gmail button",
  "version": "1.1resigned1",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8fd38aba-8a79-4a33-bdd0-98e7d7679ecc}"
    }
  }
}