diff --git a/scripts/install b/scripts/install
index d23178d..8f3c2b3 100644
--- a/scripts/install
+++ b/scripts/install
@@ -82,7 +82,7 @@ if ! yunohost app list | grep -q "id: cryptpad_sandboxing"; then
 		ynh_die "The domain $sandboxdomain provided for Cryptpad Sandboxing App is already used by another app. Please chose another one !"
 	fi
 	public=public
-	if $YNH_APP_ARG_IS_PUBLIC; then
+	if [ $is_public -eq 1 ]; then
 		yunohost app install https://github.com/YunoHost-Apps/cryptpad_sandboxing_ynh --force --args "domain=$sandboxdomain&is_$public=true"
 	else
 		yunohost app install https://github.com/YunoHost-Apps/cryptpad_sandboxing_ynh --force --args "domain=$sandboxdomain&is_$public=false"