Temporarily hide the Add button in the preferences window, as it only confuses people, pending a fuller review of the UI. r=gijs over IRC. ChatZilla only.

extensions/irc/xul/content/config.xul

@@ -87,9 +87,11 @@
           <treechildren id="pref-tree"/>
         </tree>
         <hbox>
+          <!--
           <button label="&object.add.label;" tooltiptext="&object.add.hint;" 
               accesskey="&object.add.accesskey;" flex="1" 
               oncommand="gPrefWindow.onAddObject();"/>
+          -->
           <button label="&object.del.label;" tooltiptext="&object.del.hint;" 
               accesskey="&object.del.accesskey;" flex="1" 
               oncommand="gPrefWindow.onDeleteObject();" id="object-delete"/>