When working in Windows with multiple monitors that have different display scales - dragging a window that contains a DataGrid with frozen columns would often lead to the frozen columns not getting rendered correctly. The frozen columns seem to not take into account the Dpi of the new monitor, but of the old one.

A NullReferenceException is thrown during the measure phase of a DataGridTextColumn when a CellRenderer is applied:

Object reference not set to an instance of an object.
   at Telerik.Maui.Controls.DataGrid.DataGridColumn.MeasureDrawingPaintable(LambdaPaintable lambdaPaintable, Object measureContext)
   at Telerik.Maui.Controls.SkiaSharp.SkiaLambdaPainter.Measure(MeasureablePaintable paintable, PurePainterContext context, Double widthConstraint, Double heightConstraint)
   at Telerik.Maui.Controls.DataGrid.MasterArranger.MeasureNodeContainer(Object container, Double widthConstraint)
   at Telerik.Maui.Controls.DataGrid.MasterArranger.MeasureNodeContainer(Object container, Double widthConstraint)
   at Telerik.Maui.Controls.DataGrid.MasterArranger.MeasureGridCellModel(GridCellModel model)
   at Telerik.Maui.Controls.DataGrid.CellModelGenerator.GetSize(GridCellModel decorator)
   at Telerik.Maui.Controls.DataGrid.CellsController`1.GenerateCellsForRow(IItemInfoNode rowModel, Int32 rowSlot)
   at Telerik.Maui.Controls.DataGrid.NodePool`2.GenerateModelsForInfos(IList`1 itemInfos, ModelGenerationContext modelGenerationContext, MeasureContext measureContext)
   at Telerik.Maui.Controls.DataGrid.NodePool`2.MeasureForward(MeasureContext& context)
   at Telerik.Maui.Controls.DataGrid.NodePool`2.MeasureVertically(RadSize availableSize, Double offset, Double verticalBuffer)
   at Telerik.Maui.Controls.DataGrid.NodePool`2.OnMeasure(RadSize availableSize, Double offset, Double verticalBuffer)
   at Telerik.Maui.Controls.DataGrid.GridModel.MeasureCells(RadSize availableSize)
   at Telerik.Maui.Controls.DataGrid.DataGridContentLayout.Measure(Double widthConstraint, Double heightConstraint)
   at Microsoft.Maui.Platform.MauiPanel.MeasureOverride(Size availableSize)
   at ABI.Microsoft.UI.Xaml.IFrameworkElementOverrides.Do_Abi_MeasureOverride_0(IntPtr thisPtr, Size availableSize, Size* result)

When a column in the DataGrid is being resized and is subsequently scrolled out of the viewport, a NullReferenceException is thrown. This happens because the column's model is recycled while the resize operation is still in progress. As a result, the resize logic attempts to access a column from a recycled (and now null) model, leading to the exception.

An ArgumentException is thrown in the DataGrid when updating a property that exists only on a derived type of an object used in the grid's data source. This occurs specifically when a DelegateAggregateDescriptor is applied to a column.

When the value of a property used in a PropertyAggregateDescriptor changes, and the aggregate is displayed in the group header with GroupAggregatesAlignment="NextToHeader", the header does not reflect the updated aggregate result. This issue also occurs when RenderMode is set to SkiaSharp.

when setting a custom font to the column header style, the DataGrid crashes with null ref exception on WinUI.

If you use FooterContentTemplate to add elements into the footer that require mouse over/click events (eg a Button or a Label with a tooltip), it works fine as long as the datagrid has enough data to scroll. However, if you resize the grid bigger or remove items until you no longer need to scroll and you have empty space between the last row and the footer, then none of those mouse events work.

Delegate aggregate descriptor does not update value in the UI when adding/removing item.

The behavior also happens with the property aggregate descriptor.

Aggregates error appears in column with nested properties when the data you want to group by is not set by the time the data grid's ItemsSource is set,

If the data you want to group by is not set by the time the data grid's ItemsSource is set, then the grouping doesn't work as expected. Everything gets into a single group called (blank)

When using ImageButton inside a CellTemplate, the image does not display initially. When you resize the window image is displayed. 

 

Workaround:

Use Image instead of ImageButton

 

When DataGrid is grouped and applying filtering, aggregates footer appears in the cells

expand a row and collapse it. Or expand a few rows, scroll around a bit, and then collapse one. You can get into some weird situations. Gray background over the group, row background and alternate styles are reset. 

Some data is missing from the UI when grouping is applied and then filter the data. 

If you ungroup, the items are displayed.

Starting with v10, all groups except the last, get a blank, empty row.

If you toggle off the grouping, the empty rows go away, but once you put the grouping on, these empty rows show up again.

Keep the data grouped, make the window a bit smaller so you have a decent amount of rows to scroll through, and using your mouse wheel, scroll up and down quickly. Eventually you'll notice that the grid will start to bounce a bit. For example, you'll scroll down and then without scrolling the mouse wheel up at all, it'll jump back up a few rows on its own.

When entering a cell in edit mode its value is displayed on the next cell and the cell editor template uses MaskedEntry.

Begin editing the first cell firs column
Without closing the cell editor, scroll down to the last cell, the first cell should exit the viewport.
Start editing the last cell.
Scroll back up to the first cell

The content inside the first cell is missing.

The content should be there.

when loading same page without navigating to another page, there are some left instances of the DataGrid and the memory increase. 

When a ComboBox editor is open in the DataGrid, one can use the arrow keys to go up and down the items of the combo in order to make a selection. When pressing Enter it is expected that the ComboBox gets closed and the DataGrid is still in edit mode for the same cell.

However, when the Enter is pressed - the ComboBox closes and the next row goes into edit mode - this behavior is erroneous.