             Template.tagbox.add_tag(@_id, @my_tags, tag_text, tag_box)
           when 75 #K/Kill
             Session.get("suggestions_#{ @_id }").remove(tag_text)
-            Session.get("context_#{@_id}").invalidate()
+            Session.get("context_#{@_id}")?.invalidate()
           
         event.stopImmediatePropagation()
     

          when 39 #Right-arrow: REMOVE SUGGESTED TAG
            if event.ctrlKey
              Session.get("suggestions_#{ @_id }").remove(suggested_tag)
              Session.get("context_#{@_id}").invalidate()
          else    #Update filter with new text
            Session.set("filter_text_#{ @_id }", entered_text)
            Session.get("context_#{@_id}").invalidate()
          
        event.stopImmediatePropagation()
        

        Session.set("tagging_#{ @_id }", true)  #Display tagbox
        
        Session.set("suggestions_#{ @_id }",
          if @suggestions? then @suggestions else ['tag'])
        
        event.stopImmediatePropagation()
        
