--- old/modules/jdk.packager/src/main/resources/com/sun/javafx/tools/packager/Bundle.properties	2017-12-21 17:29:32.000000000 -0800
+++ new/modules/jdk.packager/src/main/resources/com/sun/javafx/tools/packager/Bundle.properties	2017-12-21 17:29:32.000000000 -0800
@@ -83,6 +83,8 @@
 \          limit the universe of observable modules\n\
 \  --strip-native-commands <true/false>\n\
 \          include or exclude the native commands\n\
+\  -singleton\n\
+\          prevents multiple instances of the application from launching.\n\
 \  -title <title>\n\
 \          title of the application.\n\
 \  -vendor <vendor>\n\