right-click on perspective tab generates excpetion in development mode

When right-clicking on a perspective tab, I get an exception when running the cms in development mode.
This probably translates to a non-responsive application in production.

org.apache.wicket.WicketRuntimeException: The component(s) below failed to render. A common problem is that you have added a component in code but forgot to reference it in the markup (thus the component will never be rendered).

1. [MarkupContainer [Component id = contextMenu]]
2. [MarkupContainer [Component id = editor-close]]
3. [MarkupContainer [Component id = editor-close-others]]
4. [MarkupContainer [Component id = editor-close-all]]
5. [MarkupContainer [Component id = editor-close-unmodified]]

at org.apache.wicket.Page.checkRendering(Page.java:1181)
at org.apache.wicket.Page.endComponentRender(Page.java:429)
at org.apache.wicket.ajax.AjaxRequestTarget.respondComponent(AjaxRequestTarget.java:862)
at org.apache.wicket.ajax.AjaxRequestTarget.respondComponents(AjaxRequestTarget.java:682)
at org.apache.wicket.ajax.AjaxRequestTarget.respond(AjaxRequestTarget.java:592)
at org.apache.wicket.request.AbstractRequestCycleProcessor.respond(AbstractRequestCycleProcessor.java:105)
at org.hippoecm.frontend.PluginRequestCycleProcessor.respond(PluginRequestCycleProcessor.java:50001)
at org.apache.wicket.RequestCycle.processEventsAndRespond(RequestCycle.java:1258)