java.lang.IllegalArgumentException: button doesn't exist 12
        at java.awt.event.InputEvent.getMaskForButton(InputEvent.java:233)
        at java.awt.Robot.<init>(Robot.java:101)
        at org.netbeans.core.windows.view.ui.WindowSnapper.<init>(WindowSnapper.java:66)
        at org.netbeans.core.windows.view.ui.DefaultSeparateContainer$ModeDialog.<init>(DefaultSeparateContainer.java:262)
        at org.netbeans.core.windows.view.ui.DefaultSeparateContainer.<init>(DefaultSeparateContainer.java:92)
        at org.netbeans.core.windows.view.ModeView.<init>(ModeView.java:92)
        at org.netbeans.core.windows.view.ViewHierarchy.updateViewForAccessor(ViewHierarchy.java:293)
        at org.netbeans.core.windows.view.ViewHierarchy.updateSeparateViews(ViewHierarchy.java:318)
        at org.netbeans.core.windows.view.ViewHierarchy.updateViewHierarchy(ViewHierarchy.java:155)
        at org.netbeans.core.windows.view.DefaultView.changeGUI(DefaultView.java:149)
        at org.netbeans.core.windows.ViewRequestor.dispatchRequest(ViewRequestor.java:269)
        at org.netbeans.core.windows.ViewRequestor.processRequest(ViewRequestor.java:245)
        at org.netbeans.core.windows.ViewRequestor.postRequest(ViewRequestor.java:183)
        at org.netbeans.core.windows.ViewRequestor.scheduleRequest(ViewRequestor.java:123)
        at org.netbeans.core.windows.Central.setModeSelectedTopComponent(Central.java:723)
        at org.netbeans.core.windows.WindowManagerImpl.topComponentRequestVisible(WindowManagerImpl.java:1189)
        at org.openide.windows.TopComponent.requestVisible(TopComponent.java:804)
        at org.openide.text.CloneableEditor.ensureVisible(CloneableEditor.java:1000)
        at org.openide.text.CloneableEditorSupport.openAtImpl(CloneableEditorSupport.java:2442)
        at org.openide.text.CloneableEditorSupport.openReuse(CloneableEditorSupport.java:2413)
        at org.openide.text.EditorSupportLineSet$SupportLine.show(EditorSupportLineSet.java:128)
        at org.openide.text.Line.show(Line.java:324)
        at org.netbeans.modules.ruby.debugger.EditorUtil$1.run(EditorUtil.java:160)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:235)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:603)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:286)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:201)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:191)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:186)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:178)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:139)