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Using RowDetailsVisibilityMode="VisibleWhenSelected" and GridViewToggleRowDetailsColumn together:
Before expanding a row using the toggle, selecting/de-selecting it will show/hide the row details.
After expanding a row using the toggle, selecting/de-selecting it doesn't not show/hide the row details.
Before expanding a row using the toggle, selecting/de-selecting it will show/hide the row details.
After expanding a row using the toggle, selecting/de-selecting it doesn't not show/hide the row details.