Title: WP 5.9 and PHP 8.1 errors
Last modified: December 18, 2021

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# WP 5.9 and PHP 8.1 errors

 *  Resolved [ABCdatos](https://wordpress.org/support/users/abcdatos/)
 * (@abcdatos)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/wp-5-9-and-php-8-1-errors/)
 * Hi:
 * I found these errors when testing my site with WP 5.9 beta 3 and PHP 8.1
 *     ```
       PHP Deprecated:  Constant FILTER_SANITIZE_STRING is deprecated in [...]/wp-content/plugins/wordpress-seo/src/integrations/admin/helpscout-beacon.php on line 99
       PHP Deprecated:  Constant FILTER_SANITIZE_STRING is deprecated in [...]/wp-content/plugins/wordpress-seo/src/conditionals/admin/estimated-reading-time-conditional.php on line 46
       PHP Deprecated:  Constant FILTER_SANITIZE_STRING is deprecated in [...]/wp-content/plugins/wordpress-seo/src/conditionals/third-party/elementor-edit-conditional.php on line 22
       PHP Deprecated:  Constant FILTER_SANITIZE_STRING is deprecated in [...]/wp-content/plugins/wordpress-seo/src/conditionals/third-party/elementor-edit-conditional.php on line 28
       ```
   
 * Regards. Have a nice day.
    -  This topic was modified 4 years, 7 months ago by [ABCdatos](https://wordpress.org/support/users/abcdatos/).

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

 *  [Suwash Kunwar](https://wordpress.org/support/users/suascat_wp/)
 * (@suascat_wp)
 * [4 years, 7 months ago](https://wordpress.org/support/topic/wp-5-9-and-php-8-1-errors/#post-15177333)
 * [@musman12](https://wordpress.org/support/users/musman12/)
 * At the moment we support PHP 8 but we do work towards PHP 8.1 compatibility. 
   WordPress and Yoast are not yet fully compatible yet with it.
 * Once the specific version is supported all of our customers and users will be
   informed, via our newsletter and changelog updates.
 * The current workaround would be to downgrade PHP to v8.0 version.
 * If you are interested in learning more about PHP 8 compatibility, please have
   a look at our [2020 WordPress and PHP 8 compatibility](https://developer.yoast.com/blog/the-2020-wordpress-and-php-8-compatibility-report/)
   reports.
 *  Plugin Support [Michael Tiña](https://wordpress.org/support/users/mikes41720/)
 * (@mikes41720)
 * [4 years, 6 months ago](https://wordpress.org/support/topic/wp-5-9-and-php-8-1-errors/#post-15200037)
 * Hello,
 * We’ll be setting this thread to resolved to keep the forum overview.
 * Thank you!

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

The topic ‘WP 5.9 and PHP 8.1 errors’ is closed to new replies.

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## Tags

 * [constant](https://wordpress.org/support/topic-tag/constant/)
 * [php](https://wordpress.org/support/topic-tag/php/)

 * 2 replies
 * 3 participants
 * Last reply from: [Michael Tiña](https://wordpress.org/support/users/mikes41720/)
 * Last activity: [4 years, 6 months ago](https://wordpress.org/support/topic/wp-5-9-and-php-8-1-errors/#post-15200037)
 * Status: resolved