fix #3675

This looks to just be better on .net framework...

src/BizHawk.Client.EmuHawk/CustomControls/InputRoll/InputRoll.cs

@@ -267,7 +267,11 @@ namespace BizHawk.Client.EmuHawk
 
 					if (_selectedItems.Max(s => s.RowIndex) >= _rowCount)
 					{
+#if NETFRAMEWORK
+						_selectedItems.RemoveAll(i => i.RowIndex >= _rowCount);
+#else
 						_selectedItems.RemoveWhere(i => i.RowIndex >= _rowCount);
+#endif
 					}
 
 					RecalculateScrollBars();

src/BizHawk.Common/Extensions/CollectionExtensions.cs

@@ -247,7 +247,7 @@ namespace BizHawk.Common.CollectionExtensions
 			else
 			{
 				foreach (var item in list.Where(item => match(item)) // can't simply cast to Func<T, bool>
-							.ToList()) // very important
+							.ToArray()) // very important
 				{
 					list.Remove(item);
 				}