Examine source code of Quick dic

{
  "manifest_version": 2,
  "name": "Quick dic",
  "version": "1.65",
  "description": "Speedy dictionary lookup with a nice popup on double click",
  "icons": {
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  },
  "applications": {
    "gecko": {
      "id": "{d52621cf-4a11-4e55-90c4-99ab478a2ff9}"
    }
  },
  "permissions": [
    "<all_urls>",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "userscript.js"
      ],
      "run_at": "document_end"
    }
  ],
  "web_accessible_resources": [
    "dictionary.json"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self'"
}