Strange bug with information window

Normally, on any study, you can press “i” and get information on the Dicom tags of the study.
When you are through with looking at the information window, X-out the window and it goes away.
I can’t reliably reproduce this bug, so I am curious to know if others see it.
A Console window will pop up with this:

Exception in thread "AWT-EventQueue-1" java.lang.IllegalArgumentException: null source
	at java.util.EventObject.<init>(EventObject.java:56)
	at java.awt.AWTEvent.<init>(AWTEvent.java:337)
	at java.awt.event.InvocationEvent.<init>(InvocationEvent.java:285)
	at java.awt.event.InvocationEvent.<init>(InvocationEvent.java:174)
	at sun.awt.X11.XBaseMenuWindow.dispose(XBaseMenuWindow.java:907)
	at java.awt.MenuComponent.removeNotify(MenuComponent.java:310)
	at java.awt.Menu.removeNotify(Menu.java:198)
	at java.awt.Component.removeNotify(Component.java:6991)
	at java.awt.Container.removeNotify(Container.java:2816)
	at java.awt.Container.removeNotify(Container.java:2800)
	at java.awt.Window.removeNotify(Window.java:782)
	at java.awt.Frame.removeNotify(Frame.java:1041)
	at java.awt.Window$1DisposeAction.run(Window.java:1190)
	at java.awt.Window.doDispose(Window.java:1205)
	at java.awt.Window.dispose(Window.java:1147)
	at ij.text.TextWindow.close(TextWindow.java:292)
	at ij.text.TextWindow.close(TextWindow.java:264)
	at ij.text.TextWindow.processWindowEvent(TextWindow.java:254)
	at java.awt.Window.processEvent(Window.java:2009)
	at java.awt.Component.dispatchEventImpl(Component.java:4872)
	at java.awt.Container.dispatchEventImpl(Container.java:2287)
	at java.awt.Window.dispatchEventImpl(Window.java:2719)
	at java.awt.Component.dispatchEvent(Component.java:4698)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:747)
	at java.awt.EventQueue.access$300(EventQueue.java:103)
	at java.awt.EventQueue$3.run(EventQueue.java:706)
	at java.awt.EventQueue$3.run(EventQueue.java:704)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:77)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)
	at java.awt.EventQueue$4.run(EventQueue.java:720)
	at java.awt.EventQueue$4.run(EventQueue.java:718)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:77)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:717)
	at org.GNOME.Accessibility.AtkWrapper$5.dispatchEvent(AtkWrapper.java:697)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

It isn’t clear to me what the null source is - that data itself is still displayed on the screen.
It is only the information window which I have just X’ed out.

In short, does anyone else see this?
Thanks,
Ilan

I have seen it before, specifically on Linux with Java 7.

Are you running Linux with Java 7? If you upgrade to Java 8, does the problem disappear?