diff --git a/phpstan.neon b/phpstan.neon
index 07d82270..cc0a5e08 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -6,5 +6,7 @@ parameters:
 	level: 5
 	phpVersion: 80100
 	reportUnmatchedIgnoredErrors: false
+	scanDirectories:
+		- vendor/symfony/polyfill-mbstring
 	paths:
 		- src