--- a/ui/winui/button.cpp	Wed Oct 30 10:14:47 2024 +0100
+++ b/ui/winui/button.cpp	Wed Oct 30 11:07:52 2024 +0100
@@ -287,7 +287,7 @@
 		// get or create the group name
 		static int groupCount = 0;
 		winrt::hstring groupName;
-		if (radioButtons->size == 0) {
+		if (cxListSize(radioButtons) == 0) {
 			groupName = winrt::to_hstring(groupCount++);
 		} else {
 			UiWidget* firstButtonWidget = (UiWidget*)cxListAt(radioButtons, 0);