Examine source code of Page Screenshotx

{
  "manifest_version": 2,
  "name": "Page Screenshot",
  "version": "1.0",
  "description": "Capture a screenshot of the current page.",
  "permissions": [
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{42d21aa2-195f-4def-a1c9-6724aa7fe266}"
    }
  }
}