diff --git a/scripts/custom-docker-build b/scripts/custom-docker-build
index 33a03cc..f70efcb 100755
--- a/scripts/custom-docker-build
+++ b/scripts/custom-docker-build
@@ -64,7 +64,8 @@ function print_chrome_args() {
             ;;
         *) echo "Unknown chrome version $1"; exit 1;
     esac
-    printf -- "--build-arg CHROME_VERSION=%s --build-arg=CHROME_DRIVER_VERSION=%s " "$CHROME_VERSION" "$CHROME_DRIVER_VERSION"
+    printf -- "--build-arg CHROME_VERSION=%s " "$CHROME_VERSION"
+    printf -- "--build-arg CHROME_DRIVER_VERSION=%s " "$CHROME_DRIVER_VERSION"
 }
 
 function print_git_args() {