This is apparently a tape defect that has been fixed in the latest version in sound control, but not yet in the latest released version.
Now you can get around this using the following
// During initialisation myRibbon.Menu.AddHandler(PopupService.DismissPopupEvent, (DismissPopupEventHandler)OnPopupDismiss); private void OnPopupDismiss(object sender, DismissPopupEventArgs e) { var backstage = Menu as Backstage; if (backstage != null) { backstage.IsOpen = false; } }
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