NPE in Simantics Export Core

java.lang.NullPointerException: null
	at org.simantics.export.core.manager.Content.equals(Content.java:58)
	at org.eclipse.collections.impl.map.mutable.UnifiedMap.nonNullTableObjectEquals(UnifiedMap.java:3297)
	at org.eclipse.collections.impl.map.mutable.UnifiedMap.get(UnifiedMap.java:889)
	at org.simantics.utils.datastructures.MapList.getValues(MapList.java:237)
	at org.simantics.export.core.manager.ExportGroupCreateAction.execute(ExportGroupCreateAction.java:117)
	at org.simantics.export.core.manager.ExportManager.execute(ExportManager.java:58)
	at org.simantics.export.ui.ExportCoreWizard$1.run(ExportCoreWizard.java:97)
	at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:122)