Examine source code of Read Mode

{
  "manifest_version": 2,
  "name": "Read Mode",
  "version": "1.0",
  "description": "Convert web pages into a simplified reading mode for easier reading. This extension hides distracting elements such as headers, footers, advertisements, images, and videos, allowing users to focus solely on the main text content of the webpage.",
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1d97a4ab-ec35-4035-897d-05f23efd2c96}"
    }
  }
}