diff --git a/os/emscripten/deploy-webapp.sh b/os/emscripten/deploy-webapp.sh
index dc0a8c9db7..2f28a9c314 100755
--- a/os/emscripten/deploy-webapp.sh
+++ b/os/emscripten/deploy-webapp.sh
@@ -2,6 +2,7 @@
 
 INSTALL_PATH=`pwd`/../../../openttd-touch-webapp
 MESSAGE="`git log --format=%B -n 1 HEAD`"
+[ -n "$1" ] && MESSAGE="$1"
 
 export NO_CLEAN=1