Examine source code of Jun88 Screenshot

{
  "manifest_version": 2,
  "name": "Jun88 Screenshot",
  "version": "1.0",
  "description": "A simple screenshot extension for Firefox",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "<all_urls>",
    "activeTab",
    "downloads"
  ],
  "browser_action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "Jun88 Screenshot"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{fa1a319b-a4ca-4c78-8b02-c13ed6a53887}"
    }
  }
}