diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 9b28866..b2191b7 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -1,7 +1,10 @@
 #!/bin/sh
 if ! which -- "${1}"; then
   # first arg is not an executable
-  rm /tmp/.X99-lock -f > /dev/null || ``
+  if [ -e /tmp/.X99-lock ]
+  then
+    rm /tmp/.X99-lock -f
+  fi
   export DISPLAY=:99
   Xvfb "${DISPLAY}" -nolisten unix &
   exec node /usr/src/app/ "$@"