Examine source code of Tabs to Markdown

{
  "manifest_version": 2,
  "name": "Tabs to Markdown",
  "version": "1.3",
  "description": "Converts all open tabs into a list of links in a Markdown file.",
  "author": "Maxwell Wine <developer.user.contact@protonmail.com>",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_title": "Tabs to Markdown",
    "default_popup": "popup/index.html"
  },
  "permissions": [
    "contextMenus",
    "tabs",
    "downloads"
  ],
  "commands": {
    "convert-tabs-to-markdown": {
      "suggested_key": {
        "default": "Ctrl+Alt+M"
      },
      "description": "Convert all open tabs to markdown"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "index.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d296b211-4f3b-4caa-b28a-ba7e5b7ceaea}"
    }
  }
}