Examine source code of Focus Mode Toggle

{
  "manifest_version": 2,
  "name": "Focus Mode Toggle",
  "version": "1.0.0",
  "description": "Toggle a clean, distraction‑free reading mode on any page: hide sidebars and comment sections, and apply a soft focus filter.",
  "icons": {
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_action": {
    "default_title": "Focus Mode",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{b35ca20b-56d2-4262-a3f2-161c1c2ba011}",
      "strict_min_version": "109.0"
    }
  }
}