Examine source code of Simple Page Navigator

{
  "manifest_version": 2,
  "name": "Simple Page Navigator",
  "version": "1.0",
  "description": "Press Alt+N to click the 'Next' button and Alt+P to click the 'Previous' button on a page.",
  "icons": {
    "48": "icon.png"
  },
  "permissions": [
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "background": {
    "scripts": [
      "popup.js"
    ],
    "persistent": false
  },
  "commands": {
    "next-page": {
      "suggested_key": {
        "default": "Alt+N"
      },
      "description": "Click the 'Next' button"
    },
    "previous-page": {
      "suggested_key": {
        "default": "Alt+P"
      },
      "description": "Click the 'Previous' button"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a959c89e-0587-4447-98fa-245acfbae6d1}"
    }
  }
}