Examine source code of Positive Button

{
  "manifest_version": 2,
  "name": "Positive Button",
  "version": "1.0.5",
  "description": "Cliquez et Souriez",
  "permissions": [
    "contextMenus",
    "tabs"
  ],
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "browser_action": {
    "default_popup": "popup.html"
  }
}