https://manpages.ubuntu.com/manpages/xenial/man3/XmCascadeButtonHighlight.3.html
Ubuntu Manpage: XmCascadeButtonHighlight - A CascadeButton and CascadeButtonGadget function that...
A CascadeButton and CascadeButtonGadget function that sets the highlight state "XmCascadeButtonHighlight" "CascadeButton functions" "XmCascadeButtonHighlight"
ubuntumanpagefunction