Examine source code of New Tab After Current 2

{
  "manifest_version": 2,
  "name": "Custom Tab Behavior",
  "version": "1.0",
  "description": "Adds a custom shortcut to open a new tab after the current one.",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "commands": {
    "open-tab-after-current": {
      "suggested_key": {
        "default": "Ctrl+3"
      },
      "description": "Open a new tab after the current one"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3d2ee835-aebc-484e-b74b-1dec4255d0c4}"
    }
  }
}