No SysteMessages after mirgration to 7.3


I migrated a Vaadin app from 7.1 to 7.3 by replacing only the Libs. After the migration the SystemMessages (outOfSync, SessionExpired, InternalError,…) are not longer shown in browser. Any ideas what could be wrong?


I found the problem by my self. The styles for the system message in my own theme does not match. :-/