Popup menu sometimes hides partially behind the system dock, or runs out of screen. The menu items are not accessible.
More details about when this happens in NetBeans can be found in the bug at:
http://netbeans.org/bugzilla/show_bug.cgi?id=209572
Screenshots:
http://bugzilla-attachments-209572.netbeans.org/bugzilla/attachment.cgi?id=116728
http://bugzilla-attachments-209572.netbeans.org/bugzilla/attachment.cgi?id=116721
http://bugzilla-attachments-209572.netbeans.org/bugzilla/attachment.cgi?id=116720