Title: Critical CSS Code Disappears
Last modified: May 16, 2023

---

# Critical CSS Code Disappears

 *  Resolved [carmpocalypse](https://wordpress.org/support/users/carmpocalypse/)
 * (@carmpocalypse)
 * [3 years ago](https://wordpress.org/support/topic/critical-css-code-disappears/)
 * Hello,
   When hitting save after adding the critical css snippet in to ‘Eliminate
   render-blocking CSS?’ section in the plugin, the code disappears from the box.

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years ago](https://wordpress.org/support/topic/critical-css-code-disappears/#post-16740527)
 * that is likely due the CSS containing URL’s (for background images or fonts) 
   that have e.g. `wp-content/themes/themename/css/../images/background-image.jpg`
   which a security component (“web application firewall”) block because it (vaguely)
   resembles a directory traversal attack. as a workaround you’ll have to “resolve”
   the URL into one without the `../` where the previous example becomes `wp-content/
   themes/themename/images/background-image.jpg`
 * hope this helps,
    frank
 *  Thread Starter [carmpocalypse](https://wordpress.org/support/users/carmpocalypse/)
 * (@carmpocalypse)
 * [3 years ago](https://wordpress.org/support/topic/critical-css-code-disappears/#post-16742841)
 * [@optimizingmatters](https://wordpress.org/support/users/optimizingmatters/)
 * Thanks for the info. Yeah, I use Sucuri Firewall/CDN.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Critical CSS Code Disappears’ is closed to new replies.

 * ![](https://ps.w.org/autoptimize/assets/icon-256X256.png?rev=2211608)
 * [Autoptimize](https://wordpress.org/plugins/autoptimize/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/autoptimize/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/autoptimize/)
 * [Active Topics](https://wordpress.org/support/plugin/autoptimize/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/autoptimize/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/autoptimize/reviews/)

 * 2 replies
 * 2 participants
 * Last reply from: [carmpocalypse](https://wordpress.org/support/users/carmpocalypse/)
 * Last activity: [3 years ago](https://wordpress.org/support/topic/critical-css-code-disappears/#post-16742841)
 * Status: resolved