function getPopups() {
		return InstanceManager.getOpenDialogs()
		.concat(
			InstanceManager.getOpenPopovers(),
			BusyIndicator.oPopup && BusyIndicator.oPopup.isOpen() ? [BusyIndicator.oPopup] : []
		);
	}
Utility class to calculate the next available z-index.

@namespace
@author SAP SE
@version ${version}

@private
@since 1.64
@alias sap.ui.dt.util.ZIndexManager