Examine source code of Night Reader

{
  "manifest_version": 2,
  "name": "Night Reader for Firefox",
  "description": "Reading comfortably with inverted brightness but preserved hue",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png",
    "256": "icons/icon-256.png"
  },
  "version": "1.7.42resigned1",
  "content_scripts": [
    {
      "matches": [
        "*://*/*",
        "http://*/*",
        "https://*/*",
        "ftp://*/*",
        "file://*/*"
      ],
      "js": [
        "autotoggle.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "background": {
    "scripts": []
  },
  "browser_action": {
    "default_icon": "icons/icon-32.png",
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab",
    "storage",
    "http://*/*",
    "https://*/*",
    "ftp://*/*",
    "file://*/*"
  ],
  "applications": {
    "gecko": {
      "id": "{d464c6fa-2976-4e0a-a2d8-8a9a372c5dd8}"
    }
  }
}