org.netbeans.editor.GuardedException: Attempt to remove from guarded block at position 776.
	at org.netbeans.editor.GuardedDocument.preRemoveCheck(GuardedDocument.java:192)
	at org.netbeans.editor.BaseDocument.remove(BaseDocument.java:741)
	at org.netbeans.modules.diff.builtin.visualizer.editable.EditableDiffView.rollback(EditableDiffView.java:366)
	at org.netbeans.modules.diff.builtin.visualizer.editable.LineNumbersActionsBar.performAction(LineNumbersActionsBar.java:166)
	at org.netbeans.modules.diff.builtin.visualizer.editable.LineNumbersActionsBar.mouseClicked(LineNumbersActionsBar.java:173)
	at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:253)
	at java.awt.Component.processMouseEvent(Component.java:6041)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3260)
	at java.awt.Component.processEvent(Component.java:5803)
	at java.awt.Container.processEvent(Container.java:2058)
	at java.awt.Component.dispatchEventImpl(Component.java:4410)
	at java.awt.Container.dispatchEventImpl(Container.java:2116)
	at java.awt.Component.dispatchEvent(Component.java:4240)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4322)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3995)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3916)
	at java.awt.Container.dispatchEventImpl(Container.java:2102)
	at java.awt.Window.dispatchEventImpl(Window.java:2429)
	at java.awt.Component.dispatchEvent(Component.java:4240)
[catch] at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)