Examine source code of Checkly

{
  "manifest_version": 2,
  "name": "Checkly",
  "version": "1.1resigned1",
  "description": "Check all checkboxes in the web page.",
  "icons": {
    "48": "icons/checkly-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://joshmacdonald.net/*"
      ],
      "js": [
        "checkly.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{87c21b1f-4ee2-4d52-abd5-3123dc4ae141}"
    }
  }
}