When switching to NetBeans using Alt+Tab the menubar in netbeans is activated (like when pressing "alt" when in Netbeans).
This causes problems when you try to write something after switching to netbeans with alt+tab, cause all keys are
interpereted as menu-shortcuts.
Known bug in Swing, already reported in 73960, but thanks anyway.
*** This issue has been marked as a duplicate of 73960 ***