2593329 - Introscope Webview error "....failed for : com.ca.apm.introscope.workstation.webapp.server.models.DashboardDetailsModel" when viewing dashboard with custom metrics

Introscope Webview does not show the dashboard custom metrics. A Null pointer exception (NPE) is thrown:

 [ERROR] [WebView] Identifier: 1001.1516086759 - receiveMessage() failed for : com.ca.apm.introscope.workstation.webapp.server.models.DashboardDetailsModel::2002
java.lang.NullPointerException
        at com.ca.apm.introscope.workstation.webapp.server.dashboard.DashboardDataTracker.getData(DashboardDataTracker.java:173)
        at com.ca.apm.introscope.workstation.webapp.server.models.DashboardDetailsModel.receiveMessage(DashboardDetailsModel.java:167)
        at com.ca.apm.introscope.workstation.webapp.server.models.ModelManager$ModelRequestThread$1.run(ModelManager.java:483)
        at java.lang.Thread.run(Thread.java:722)

Solution Manager 7.1 SP12 and above

Introscope 9.7

Introscope Webview Workstation Custom Metrics DashboardDetailsModel , KBA , XX-PART-WILY , Introscope by CA Technologies , Problem