diff --git a/composer.json b/composer.json
index 7f64c8b..e9c4c98 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
 	],
 	"require":{
 		"php":">=5.3",
-		"contao/core":">=3.5.1,<4.2",
+		"contao/core":">=3.5.1,<5",
 		"contao-community-alliance/composer-plugin": "~2.0"
 	},
 	"replace": {