diff --git a/src/_includes/install/php-versions-2.4.md b/src/_includes/install/php-versions-2.4.md
index edd3c63fc44..3ced1882dc4 100644
--- a/src/_includes/install/php-versions-2.4.md
+++ b/src/_includes/install/php-versions-2.4.md
@@ -2,3 +2,4 @@ Magento supports PHP 7.4.0. You can install Magento 2.4.0 with 7.3, but it is no
 
 {:.bs-callout-warning}
 There is a [bug](https://bugs.php.net/bug.php?id=79174) in PHP 7.4.2 which causes some messages to not render properly. Magento recommends using other versions of 7.4.
+There is a [bug](https://github.com/jbboehr/php-psr/issues/78) in the `psr` php extension which causes fatal errors during installation or upgrade. Magento recommends uninstalling or deactivating the `psr` php extension.