Title: Render blocking CSS issues with optimized files
Last modified: April 22, 2026

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# Render blocking CSS issues with optimized files

 *  [ohslin](https://wordpress.org/support/users/ohslin/)
 * (@ohslin)
 * [1 month, 2 weeks ago](https://wordpress.org/support/topic/render-blocking-css-issues-with-optimized-files/)
 *  [https://ibb.co/JR7F31XX](https://ibb.co/JR7F31XX)
 * I am using Autoptimize on my website, but PageSpeed Insights is flagging the 
   generated CSS files as “Render blocking requests.”
 * According to the report (screenshot attached), these optimized files are causing
   an estimated saving loss of **930 ms**. The specific files are:
    - `autoptimize_single_49ac083....css`
    - `autoptimize_single_c8d07f6....css`
 * Could you please help me understand how to fix this? I want to move these network
   requests out of the critical path to improve my LCP and FCP scores.
 * Do I need to enable “Inline and Defer CSS”? If so, what is the recommended way
   to handle Critical CSS for these files?
 * p.s.
 * I also noticed a “Forced reflow” warning in the Insights section (screenshot 
   attached). The source is listed as `[unattributed]`, but it takes about **80 
   ms.**
 * Could this be related to how Autoptimize handles the JS/CSS execution order? 
   Any tips on how to identify the cause or if there’s a setting in the plugin to
   mitigate this would be greatly appreciated.
    -  This topic was modified 1 month, 2 weeks ago by [ohslin](https://wordpress.org/support/users/ohslin/).

Viewing 1 replies (of 1 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [1 month, 2 weeks ago](https://wordpress.org/support/topic/render-blocking-css-issues-with-optimized-files/#post-18887375)
 * You will indeed have to look at the “eliminate render-blocking CSS” option, using
   one of below four options;
 * a) generate & copy/paste the “above the fold CSS” in the field below (more info
   in the [AO FAQ](https://wordpress.org/plugins/autoptimize/faq/), look for “inline&
   defer CSS”) OR
    b) create manual rules on the “critical CSS” tab (generating 
   critical css for each rule) OR c) take a subscription over at criticalcss and
   paste your API in the field on the critical CSS tab OR d) take a subscription
   for Autoptimize Pro, which includes the automated created of critical CSS rules
 * hope this helps,
    frank

Viewing 1 replies (of 1 total)

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 * 1 reply
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [1 month, 2 weeks ago](https://wordpress.org/support/topic/render-blocking-css-issues-with-optimized-files/#post-18887375)
 * Status: not resolved