Unfortunately, there is no Visibility property of the TileGroup which value you can directly use for binding. Can you please clarify what exactly your intentions are? Would you like to hide the Group header or all the items within this specific group?
If you would like to set the visibility of all items within a certain group, you can use an approach similar to the following one:
var actualItem = item
actualItem.Visibility = Visibility.Collapsed;
Rémi, please provide more details on the behavior you are aiming for so we can consider the different options. I have attached a sample project to my reply. You can modify it so that it reflects your setup and send it over so we can further advise.
I am looking forward to your reply.
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