diff --git a/src/wp-admin/includes/update-core.php b/src/wp-admin/includes/update-core.php
index 5d37b1901b..e3ddec3db6 100644
--- a/src/wp-admin/includes/update-core.php
+++ b/src/wp-admin/includes/update-core.php
@@ -1004,7 +1004,7 @@ function update_core( $from, $to ) {
 	// Add a warning when the JSON PHP extension is missing.
 	if ( ! extension_loaded( 'json' ) ) {
 		return new WP_Error(
-			'php_not_compatible',
+			'php_not_compatible_json',
 			sprintf(
 				/* translators: 1: WordPress version number, 2: The PHP extension name needed. */
 				__( 'The update cannot be installed because WordPress %1$s requires the %2$s PHP extension.' ),