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So even for error messages, only the last message will always be visible - all the others are auto-dismissed. In order to avoid that warnings and errors are missed, not dismissed messages cause the message icon to light up. The color of this icon shall indicate the highest level of message waiting to be confirmed and a badge shall show the total number of errors and warnings which need to be read.
Messages list
A click on the messages icon shows the The list of system messages is accessible from the Monitoring work area. All messages of type error, warning and informational show up in this list - status messages do not show up on any list.
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