When the listview expands or collapses an item it notifies the parent using the TVN_ITEMEXPANDING message. The parent can return true on this message and it prevents the treeview from expanding or collapsing the item. WINE does not let you deny TVN_ITEMEXPANDING by returning true.
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=53727
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v3: comctl32/treeview: Allow treeview parent to deny treeview expansion.
comctl32/tests: Add test to check if treeview expansion can be denied.
https://gitlab.winehq.org/wine/wine/-/merge_requests/6218