message: Do not mount metrics pages when they're not visible
  Closes
diff: @@ -168,11 +168,15 @@ class AppDetails extends React.Component<AppDetailsProps, AppDetailsState> {
  const tab = (
  <Tab title={dashboard.title} key={dashboard.template} eventKey={tabKey}>
  + {this.state.currentTab === dashboard.template ? (
  <CustomMetricsContainer
  namespace={this.props.match.params.namespace}
  app={this.props.match.params.app}
  template={dashboard.template}
  />
  + ) : (
  + undefined
  + )}
  </Tab>
  );
  tabs.push(tab);
  