 	$tabButtons = {}
 
 	buttons = new ReactiveVar {}
+
+	extraGroups = {}
 
 	animating = false
 	open = new ReactiveVar false


	showGroup: showGroup
	getVisibleGroup: getVisibleGroup

		Tracker.nonreactive ->
			btns = buttons.get()
			btns[config.id] = config

			if extraGroups[config.id]?
				btns[config.id].groups ?= []
				btns[config.id].groups = _.union btns[config.id].groups, extraGroups[config.id]
				delete extraGroups[config.id]

			buttons.set btns

	removeButton = (id) ->
