Examine source code of internet filter

{
  "manifest_version": 2,
  "name": "ImageScaler0.1",
  "version": "0.1",
  "description": "Intercept image responses and scale them to 10% before delivering to the browser (Firefox).",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "background": {
    "page": "background.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "background.js",
        "cleen.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "filter@zindalino.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}