Examine source code of Tab Switcher

{
  "manifest_version": 2,
  "name": "Tab Switcher",
  "version": "1.0",
  "description": "Quickly switch between open tabs with a searchable popup.",
  "permissions": [
    "tabs",
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon.png"
    }
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dbb4871f-a0c9-4719-96fe-576f4b285bee}"
    }
  }
}