Examine source code of Tab to Popup

{
  "manifest_version": 2,
  "name": "Tab to Popup",
  "version": "1.0",
  "description": "Quickly converts the current tab or any selected link into a popup window for a distraction-free browsing experience",
  "browser_action": {
    "default_icon": "logo.png",
    "default_title": "Convert 2 Popup"
  },
  "background": {
    "persistent": false,
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "contextMenus",
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{c2815fd6-6d02-4aee-8e34-fb8f9e84909f}"
    }
  }
}