Examine source code of TabLister

{
  "manifest_version": 2,
  "name": "TabLister",
  "version": "1.0",
  "description": "Lists all open tabs in a popup window.",
  "permissions": [
    "tabs",
    "downloads"
  ],
  "browser_action": {
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{18be4320-a932-4ba4-aec8-c390067f2e17}"
    }
  }
}