Title: Filter for modifying aggregated css
Last modified: February 27, 2021

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# Filter for modifying aggregated css

 *  Resolved [raghavendra89](https://wordpress.org/support/users/raghavendra89/)
 * (@raghavendra89)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/filter-for-modifying-aggregated-css/)
 * Is there a filter for modifying aggregated css?
 * I would like to add “font-display:swap;” to all @font-face declarations. Is there
   a filter before you save the cached css file? I tried this filter: “autoptimize_css_after_minify”,
   but it is not working.
 * Thanks for the help,

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/filter-for-modifying-aggregated-css/#post-14111185)
 * there sure is; `autoptimize_css_after_minify`
 * have fun 🙂
    frank
 *  Thread Starter [raghavendra89](https://wordpress.org/support/users/raghavendra89/)
 * (@raghavendra89)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/filter-for-modifying-aggregated-css/#post-14111376)
 * yes, it works thanks.
 * And I got rid of Google warning: “Ensure text remains visible during webfont 
   load”.
 *     ```
       function cstm_add_font_display_property($css)
       {
           return str_replace('@font-face{', '@font-face{font-display:swap;', $css);
       }
       add_filter( 'autoptimize_css_after_minify', 'cstm_add_font_display_property', 10, 1 );
       ```
   
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [5 years, 3 months ago](https://wordpress.org/support/topic/filter-for-modifying-aggregated-css/#post-14111381)
 * great job raghavendra89 ! 🙂

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Filter for modifying aggregated css’ is closed to new replies.

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## Tags

 * [filter](https://wordpress.org/support/topic-tag/filter/)
 * [font](https://wordpress.org/support/topic-tag/font/)

 * 3 replies
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [5 years, 3 months ago](https://wordpress.org/support/topic/filter-for-modifying-aggregated-css/#post-14111381)
 * Status: resolved