Examine source code of Alert Sound Customizer

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "version": "1.0",
  "description": "__MSG_extensionDescription__",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": {
      "48": "icons/icon.png"
    },
    "default_title": "__MSG_extensionName__"
  },
  "icons": {
    "48": "icons/icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{83ec4e9f-39f3-416b-9ccd-e705da3fd672}"
    }
  }
}