To reproduce this:

1. Set the GroupRenderMode of RadGridView to Flat.
   
2. Page RadGridView using RadDataPager.
   
3. Scroll to the last row in the view. Or scroll to any row so that few of the rows above are not longer visible.
   
4. Expand the row details and scroll down more until only the parent row is visible.
   
5. Collapse the row details. At this point, the vertical scrollbar disappears and the upper rows are not brought into the view as expected when the row details gets collapsed.

To work this around call the Rebind() method of RadGridView on RowDetailsVisibilityChanged event.

private void RadGridView_RowDetailsVisibilityChanged(object sender, Telerik.Windows.Controls.GridView.GridViewRowDetailsEventArgs e)
{
	if (e.Visibility == Visibility.Collapsed)
	{
		this.gridView.Rebind();
	}        
}

We noticed that RadGridView does not get garbagecollected sometimes.
So i fired up  a memory analyzer to see what is going on.

This is the graph that shows that the RadGridView is causing a leak. The only references that keep the GridView from getting collected are those two WeakEventListeners

To further investigate i decompiled GridViewDataControl and could identify the culprit.

private void SubscribeToDispatcherShutdown()
    {
      if (this.dispatcherShutdownListener != null)
        this.dispatcherShutdownListener.Detach();
      this.dispatcherShutdownListener = new WeakEventListener<GridViewDataControl, object, EventArgs>(this);
      this.dispatcherShutdownListener.OnEventAction = (Action<GridViewDataControl, object, EventArgs>) ((grid, source, eventArgs) => grid.OnDispatcherShutdownFinished(source, eventArgs));
      this.dispatcherShutdownListener.OnDetachAction = (Action<WeakEventListener<GridViewDataControl, object, EventArgs>>) (weakEventListener => this.Dispatcher.ShutdownFinished -= new EventHandler(this.dispatcherShutdownListener.OnEvent));
      this.Dispatcher.ShutdownFinished += new EventHandler(this.dispatcherShutdownListener.OnEvent);
    }

In the second line from the botton

... weakEventListener => this.Dispatcher.ShutdownFinished -

Bind a grid to a DataView

Start editing and change the values of a few cells.

Press Escape twice to cancel the edit of the entire row.

Expected: the values return to the old values

Actual: the values remain the last entered ones

If you have the following model, the columns that show the Test and Date properties (in the derived class) cannot be sorted or filtered.

• Open the GridView examples
• In the available examples, select "Selection and Usability | Row Details"
• Select a row in the grid view
• In the external Details Presenter, select : nothing is displayed in the bottom.
• You have to select another row and then come back to show the detail.

The fix for this issue will be available with the next LIB (version 2018.3.1217) expected on Monday, December 17.

Setting the theme via the StyleManager.SetTheme(control, theme) method does not style the cell as expected when a CellStyle is defined for its parent column.

The current workaround is to explicitly set the theme via the style:
<Style x:Key="BlueCellStyle" TargetType="telerik:GridViewCell">
		<Setter Property="Background" Value="PowderBlue"/>
                <Setter Property="telerik:StyleManager.Theme" Value="VisualStudio2013" />
</Style>

As a workaround, the Path with the PathGeometry setter in the style can be replaced by a RadGlyph with a pin icon. The IsPinned Trigger in the style can be replaced with a DataTrigger to the parent row's IsPinned. Here's an example of the updated style for the Fluent theme:

<Style x:Key="GridViewPinButtonStyle" TargetType="grid:GridViewPinButton">
        <Setter Property="PathStyle" Value="{StaticResource PinUnpinPathStyle}"/>
        <Setter Property="Foreground" Value="{telerik1:FluentResource ResourceKey=IconBrush}"/>
        <Setter Property="MinHeight" Value="28"/>
        <Setter Property="MinWidth" Value="22"/>
        <Setter Property="IsBackgroundVisible" Value="False"/>
        <Setter Property="Command" Value="{x:Static telerik:RadGridViewCommands.TogglePinnedRowState}"/>
        <Setter Property="CommandParameter" Value="{Binding}"/>
        <Setter Property="SnapsToDevicePixels" Value="True"/>
        <Setter Property="BorderThickness" Value="0"/>
        <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
        <Setter Property="VerticalContentAlignment" Value="Stretch"/>
        <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
        <Setter Property="IsTabStop" Value="False"/>
        <Setter Property="Padding" Value="0 0 2 0"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="telerik:RadPathButton">
                    <Grid Background="Transparent">
                        <VisualStateManager.VisualStateGroups>
                            <VisualStateGroup x:Name="BackgroundVisibility">
                                <VisualState x:Name="BackgroundIsHidden">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="OuterBorder" Storyboard.TargetProperty="Visibility">
                                            <DiscreteObjectKeyFrame KeyTime="0">
                                                <DiscreteObjectKeyFrame.Value>
                                                    <Visibility>Collapsed</Visibility>
                                                </DiscreteObjectKeyFrame.Value>
                                            </DiscreteObjectKeyFrame>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="BackgroundIsVisible"/>
                            </VisualStateGroup>
                        </VisualStateManager.VisualStateGroups>
                        <Border x:Name="OuterBorder"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                BorderBrush="{TemplateBinding BorderBrush}"
                                Background="{TemplateBinding Background}"
                                CornerRadius="{TemplateBinding CornerRadius}"/>
                        <telerik:RadGlyph x:Name="UnPinIcon" Foreground="{TemplateBinding Foreground}" FontSize="16" HorizontalAlignment="Center" VerticalAlignment="Center" Glyph="{StaticResource GlyphPin}"/>
                    </Grid>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="Foreground" Value="{telerik1:FluentResource ResourceKey=AccentMouseOverBrush}"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="True">
                            <Setter Property="Foreground" Value="{telerik1:FluentResource ResourceKey=AccentPressedBrush}"/>
                        </Trigger>
                        <DataTrigger Binding="{Binding IsPinned, RelativeSource={RelativeSource AncestorType=telerik:GridViewRow}}" Value="True">
                            <Setter TargetName="UnPinIcon" Property="Glyph" Value="{StaticResource GlyphUnpin}" />
                        </DataTrigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

ArgumentException: 'RadGlyphExtension' is not valid for Setter.Value. The only supported MarkupExtension types are DynamicResourceExtension and BindingBase or derived types.

StackTrace:
   at System.Windows.Setter.Seal()
   at System.Windows.SetterBaseCollection.Seal()
   at System.Windows.Style.Seal()
   at System.Windows.Style.Seal()
   at System.Windows.StyleHelper.UpdateStyleCache(FrameworkElement fe, FrameworkContentElement fce, Style oldStyle, Style newStyle, Style& styleCache)
   at System.Windows.FrameworkElement.OnStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
   at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
   at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
   at System.Windows.DependencyObject.InvalidateProperty(DependencyProperty dp, Boolean preserveCurrentValue)
   at System.Windows.FrameworkElement.UpdateStyleProperty()
   at System.Windows.FrameworkElement.OnInitialized(EventArgs e)
   at Telerik.Windows.Controls.RadButton.OnInitialized(EventArgs e)
   at Telerik.Windows.Controls.RadPathButton.OnInitialized(EventArgs e)
   at Telerik.Windows.Controls.GridView.GridViewPinButton.OnInitialized(EventArgs e)
   at System.Windows.FrameworkElement.TryFireInitialized()
   at System.Windows.FrameworkElement.EndInit()
   at MS.Internal.Xaml.Runtime.ClrObjectRuntime.InitializationGuard(XamlType xamlType, Object obj, Boolean begin)