Examine source code of Text Inserter

{
  "manifest_version": 2,
  "name": "Text Inserter",
  "version": "1.0",
  "description": "Insert text into textarea with popup, including Space and Enter",
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Insert Text",
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{12033a34-c072-4090-97e8-ad4c060249eb}"
    }
  }
}