Examine source code of Medium Bypass

{
  "manifest_version": 2,
  "name": "Medium Bypass",
  "version": "1.0",
  "description": "Redirects medium urls to google cache version, bypassing login requirements",
  "icons": {
    "48": "icons/phoenix48.png",
    "96": "icons/phoenix96.png"
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/phoenix19.png",
      "38": "icons/phoenix38.png"
    }
  },
  "background": {
    "scripts": [
      "script.js"
    ],
    "persistent": false
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{97c45d60-8435-4327-a29a-59dc83e7c79a}"
    }
  }
}