diff --git a/phpBB/composer.json b/phpBB/composer.json
index 68d55b4d06..0ab30b0837 100644
--- a/phpBB/composer.json
+++ b/phpBB/composer.json
@@ -19,7 +19,7 @@
 		"irc": "irc://irc.freenode.org/phpbb"
 	},
 	"scripts": {
-		"post-update-cmd": "echo 'You MUST manually modify the clean-vendor-dir target in build/build.xml when adding or upgrading dependencies."
+		"post-update-cmd": "echo 'You MUST manually modify the clean-vendor-dir target in build/build.xml when adding or upgrading dependencies.'"
 	},
 	"replace": {
 		"phpbb/phpbb-core": "self.version"