Examine source code of Volume Booster

{
  "manifest_version": 2,
  "name": "Volume Booster",
  "version": "0.2",
  "description": "Boost your volume up to 500%.",
  "permissions": [
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon-48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{3e4b4578-e3d0-486e-ab0b-743fba91a5f7}"
    }
  }
}