Examine source code of Medium parser

{
  "manifest_version": 3,
  "name": "Medium Parser",
  "version": "1.6.5",
  "description": "Read medium based articles for free.",
  "icons": {
    "16": "img/icon16.jpg",
    "32": "img/icon32.jpg",
    "48": "img/icon48.jpg",
    "64": "img/icon64.jpg",
    "96": "img/icon96.jpg",
    "128": "img/icon128.jpg"
  },
  "permissions": [
    "storage",
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "action": {
    "default_icon": "img/icon128.jpg"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "app.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "medium-parser@example.com"
    }
  }
}