Why the audit is important
When your page links to another page using
target="_blank", the new page
runs on the same process as your page. If the new page is executing expensive
On top of this,
target="_blank" is also a security vulnerability. The new page
has access to your window object via
window.opener, and it can navigate your
page to a different URL using
window.opener.location = newURL.
See The Performance Benefits of rel=noopener for more information.
How to pass the audit
rel="noopener" to each of the links that Lighthouse has identified in your
report. In general, always add
rel="noopener" when you open an external link
in a new window or tab.
<a href="https://examplepetstore.com" target="_blank" rel="noopener">...</a>
How the audit is implemented
This section explains how this audit is implemented, so that you can understand how the audit's score is calculated.
Lighthouse uses the following algorithm to flag links as
- Gather all
<a>nodes that contain the attribute
target="_blank"and do not contain the attribute
- Filter out any same-host links.
Because Lighthouse filters out same-host links, there's an edge case that you
might want to be aware of if you're working on a large site. If your page opens
a link to another section of your site without using
performance implications of this audit still apply. However, you won't see these
links in your Lighthouse results.