Title: CSS Error false positive
Last modified: April 15, 2025

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# CSS Error false positive

 *  [Malae](https://wordpress.org/support/users/malae/)
 * (@malae)
 * [1 year, 1 month ago](https://wordpress.org/support/topic/css-error-false-positive/)
 * Hello,
 * I am using WordPress 6.7.2 and PHP 8.3. I have the following error showing:
   `
   Error: CSS: contain-intrinsic-size: Property contain-intrinsic-size doesn't exist.`
   This appears in `wp-includes/media.php line 268`This denoted as an error from
   the Nu Html Checker. It is listed in the W3C Working Draft, 20 May 2021 CSS Box
   Sizing Module Level 4.Does this mean the Checker is not up-to-date?

The topic ‘CSS Error false positive’ is closed to new replies.

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## Tags

 * [false positive](https://wordpress.org/support/topic-tag/false-positive/)

 * 0 replies
 * 1 participant
 * Last reply from: [Malae](https://wordpress.org/support/users/malae/)
 * Last activity: [1 year, 1 month ago](https://wordpress.org/support/topic/css-error-false-positive/)
 * Status: not resolved