Examine source code of Focus Enhancer

{
  "manifest_version": 2,
  "name": "Focus Enhancer",
  "version": "1.0",
  "description": "Enhance concentration and productivity by minimizing distractions.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "tabs",
    "storage",
    "notifications",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5cbc6e91-317e-4a33-b632-5ca7a4f3d008}"
    }
  }
}