Introduced in ToolKit v1.3.11, Booster > Headstart gives ToolKit users the ability to easily preconnect and prefetch external resources.
By “Prefetching” an external domain, browsers can begin connecting and downloading a resource faster. This helps improve load and render times and addresses the Lighthouse recommendation “Preconnect to Required Origins“
To use Headstart:
1) Perform a GTMetrix scan or Lighthouse performance audit to easily and quickly identify any external third-party resources that are being loaded on your page.
In GTMetrix, take a look at the Waterfall tab, identify any scripts that being downloaded/served from an external domain (aka any domain that is not yours).
![](https://toolkitforelementor.com/wp-content/uploads/2021/04/extdomains.png)
If using Lighthouse or web.dev instead, there will be an area “Preconnect to Required Origins”.
![](https://toolkitforelementor.com/wp-content/uploads/2021/04/prega.png)
2) In Booster > Headstart, prefetch these resources by simply adding the domains of the external resources without the ‘http:’ or ‘https:’ parts as seen in the image below.
![](https://toolkitforelementor.com/wp-content/uploads/2021/05/headstart.png)
3) Click save and clear all levels of cache!
Congrats! ToolKit will now attempt to prefetch your external resources which can help improve load and render times.