Attached is a patch that adds the Whiskermenu panel plugin for Xfce: https://goodies.xfce.org/projects/panel-plugins/xfce4-whiskermenu-plugin

I originally had GTK+ added as an input, and the configure phase searches for it, but since it builds fine without GTK+ I've removed it. If Garcon is removed then it errors on not finding GTK+, but I don't know, if it works then *shrug*.