Block resources to test your site without CSS or JavaScript

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Block resources to test your site without CSS or JavaScript

The various resources loaded by your site aren't always guaranteed to reach your users when they visit your site. Network problems can occur, JavaScript may be disabled, a CDN may be down, or the browser can decide to block a resource.

It's useful to test how your site looks when this occurs. It may also be useful to compare the performance of your site with and without certain resources.

With DevTools you can block individual URLs or more global patterns.

The Network panel in Edge showing the contextual menu with the "block request url" item.

The Network panel in Firefox showing the contextual menu with the "block url" item and the "blocking" sidebar.

See also