diff --git a/Documents/bin/update-wb b/Documents/bin/update-wb
index 9f64b0fe7bf198da833d9ec4be55f8682540bd72..a2bc3863c6adefcd6f498e91c61b3d4c26051db4 100755
--- a/Documents/bin/update-wb
+++ b/Documents/bin/update-wb
@@ -23,7 +23,7 @@ update() {
 if [ "$(hostname)" = 'toolbox' ]
 then
     /usr/libexec/flatpak-xdg-utils/flatpak-spawn --host "$0" "$@"
-elif [ "$1" = "-d" ] || [ "$1" = "--dry-run" ] || [ -n "${DRY_RUN:-}" ]
+elif [ "${1:-}" = "-d" ] || [ "${1:-}" = "--dry-run" ] || [ -n "${DRY_RUN:-}" ]
 then
     podman image pull "$IMAGE" > /dev/null
 elif ! (is_latest)