If you set a RowHeight value that is smaller than the height of a pinned row, the last row is clipped when you scroll to bottom. Based on the RowHeight and the number of pinned rows, you can have the last row partially clipped or fully clipped. Also, you can have more than one rows that are cut.

To work this around set the Padding and MinHeight properties of the GridViewPinButton.

<telerik:RadGridView.Resources>
       <!-- In case you are using NoXaml dlls, set the following property to the Style object: -->
       <!-- BasedOn="{StaticResource GridViewPinButtonStyle}" -->
	<Style TargetType="telerik:GridViewPinButton">
		<Setter Property="MinHeight" Value="0" />
		<Setter Property="Padding" Value="2" />
	</Style>
</telerik:RadGridView.Resources>

The issue reproduces in the following situation.

• The selection mode is Extended and the selection unit is Mixed.
  
• Multiple rows are selected.
  
• Cells of the selected rows are updated.
  
• The column of the updated cells is previously sorted (before the update of the cell values).
  
• DataTable is used to populate the RadGridView control.

To work this around set the SelectionUnit property of RadGridView to FullRow or use a collection type like ObservableCollection<T> instead of a DataTable.

The class Telerik.Windows.Data.QueryableExtensions has a static dictionary "providerIsEntityFrameworkCore"

That dictionary will hold a reference (forever) to a collection that is set as Source for the GridView.

Reason is that non IQueryable-types will be wrapped in a EnumerableQuery<T> that will return itself as the provider (https://referencesource.microsoft.com/#System.Core/System/Linq/SequenceQuery.cs,44), encapsulating the reference.

This must be something introduced recently.

You are able to resize columns using the columns gripper. The corresponding group will be automatically resized. We can provide a way to resize the column groups. The columns inside the group will be automatically resized with the group.

At the moment the GridViewNewRow can be placed at the top or at the bottom. Placing it between the rows will require new virtualization mechanism. 

This behavior is reproducible when the HorizontalAligment property of the control or its parent element is set to Left.

Changing the TextAlignment property of the GridViewExpressionColumn doesn't refresh the cells, thus the change is not visible in the UI.

To work this around, remove and add again the corresponding column in the Columns collection of RadGridView. Or define a CellTemplate and use a TextBlock control with its TextAlignment bound to the column's property.

<telerik:GridViewExpressionColumn.CellTemplate>
	<DataTemplate>
		<TextBlock Text="{Binding}" 
				   TextAlignment="{Binding RelativeSource={RelativeSource AncestorType=telerik:GridViewCell}, Path=Column.TextAlignment}"  />
	</DataTemplate>
</telerik:GridViewExpressionColumn.CellTemplate>

In this particular case, the DisplayIndex properties of the parent and child grid are bound to property from our ViewModel. When the parent grid columns are reordered runtime, the columns of the child grid are also reordered. But when sorting is performed by clicking on a column header, an exception is thrown.