Examine source code of ThumbTack

{
  "name": "ThumbTack",
  "version": "0.0.6resigned1",
  "version_name": "0.0.5",
  "manifest_version": 2,
  "description": "Automatically pins tabs based on URL, domain, or regular expression",
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "64": "icon-64.png",
    "128": "icon-128.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "icon-16.png",
      "32": "icon-32.png",
      "48": "icon-48.png"
    },
    "default_title": "ThumbTack"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "background": {
    "scripts": [
      "extension.js"
    ],
    "persistent": false
  },
  "permissions": [
    "tabs",
    "storage",
    "webNavigation"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{a402337a-8e5a-4379-b5b0-b33464703644}"
    }
  }
}