XojoCloud.RemoteNotifications.Message.AlertSubTitle

From Xojo Documentation

Property (As String )
aXojoCloud.RemoteNotifications.Message.AlertSubTitle = newStringValue
or
StringValue = aXojoCloud.RemoteNotifications.Message.AlertSubTitle

New in 2021r2

Supported for all project types and targets.

The subtitle of the alert, displayed below the Title using a smaller font size.