Examine source code of One Click Image Download

{
  "manifest_version": 2,
  "name": "One Click Image Download",
  "version": "1.1.1",
  "description": "Download the largest image on the current page with one click.",
  "permissions": [
    "activeTab",
    "downloads",
    "declarativeNetRequest",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_title": "Download largest image",
    "default_icon": {
      "32": "icons/icon-32.png",
      "64": "icons/icon-64.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "one-click-image-download-v2@abhishek",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  }
}