netbeans-6.8-201001171801-javafx-full.zip 

  Product Version         = NetBeans IDE 6.8 (Build 201001171801)
(#434511277c30)
  Operating System        = Windows XP version 5.1 running on x86
  Java; VM; Vendor        = 1.6.0_15; Java HotSpot(TM) Client VM 14.1-b02; Sun

Steps to reproduce:

- Create a JavaFX project
- Edit the main file 
(add new lines, format code)

After that I am not able to delete lines in the code.

There is NPE in the IDE log file:

java.lang.NullPointerException
	at org.netbeans.modules.editor.hints.AnnotationHolder.removeUpdate(AnnotationHolder.java:410)
	at org.netbeans.lib.editor.util.swing.PriorityDocumentListenerList.removeUpdate(PriorityDocumentListenerList.java:99)
	at javax.swing.text.AbstractDocument.fireRemoveUpdate(AbstractDocument.java:243)
	at org.netbeans.editor.BaseDocument.fireRemoveUpdate(BaseDocument.java:1626)
	at org.netbeans.editor.BaseDocumentEvent.undo(BaseDocumentEvent.java:312)
	at org.netbeans.editor.GuardedDocumentEvent.undo(GuardedDocumentEvent.java:69)
	at javax.swing.undo.CompoundEdit.undo(CompoundEdit.java:46)
	at org.netbeans.editor.BaseDocument$AtomicCompoundEdit.undo(BaseDocument.java:2181)
	at org.netbeans.editor.BaseDocument.breakAtomicLock(BaseDocument.java:1814)
	at org.netbeans.editor.GuardedDocument.runAtomicAsUser(GuardedDocument.java:363)
	at org.netbeans.editor.BaseKit$InsertBreakAction.actionPerformed(BaseKit.java:1185)
	at org.netbeans.modules.javafx.editor.JavaFXInsertBreakAction.actionPerformed(JavaFXInsertBreakAction.java:62)
	at org.netbeans.editor.BaseAction.actionPerformed(BaseAction.java:336)
	at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1636)
	at javax.swing.JComponent.processKeyBinding(JComponent.java:2851)
	at javax.swing.JComponent.processKeyBindings(JComponent.java:2886)
	at javax.swing.JComponent.processKeyEvent(JComponent.java:2814)
	at java.awt.Component.processEvent(Component.java:6040)
	at java.awt.Container.processEvent(Container.java:2041)
	at java.awt.Component.dispatchEventImpl(Component.java:4630)
	at java.awt.Container.dispatchEventImpl(Container.java:2099)
	at java.awt.Component.dispatchEvent(Component.java:4460)
	at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
	at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:704)
	at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:969)
	at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:841)
	at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:668)
	at java.awt.Component.dispatchEventImpl(Component.java:4502)
	at java.awt.Container.dispatchEventImpl(Container.java:2099)
	at java.awt.Window.dispatchEventImpl(Window.java:2475)
	at java.awt.Component.dispatchEvent(Component.java:4460)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
	at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:125)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
[catch] at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)