...

To fix this, set recent.submissions.count = 0 in [dspace]/config/dspace.cfg and restart your servlet container. If needed, also clear the Cocoon cache: TechnicalFaq#TechnicalFaq-ClearingCocoon(XMLUI)cache

How do I update Messages.properties without rebuilding DSpace?

The Messages.properties file is used for translations both in DSpace core ([dspace]/lib/dspace-api-4.0-SNAPSHOT.jar) and in DSpace JSPUI ([dspace]/webapps/jspui/WEB-INF/lib/dspace-api-4.0-SNAPSHOT.jar). You usually want to update the JSPUI one:

1) find dspace-api-X.X.jar in [dspace]/webapps/jspui/WEB-INF/lib/
2) unzip it in an external folder
3) modify the Message.properties file
4) copy Message.properties to [dspace]/webapps/jspui/WEB-INF/classes/
5) restart your servlet container