It seems that the default fonts in the RadDataGrid do not support some languages, for example this text "이름" cannot be displayed in Android and WinUI. Rectangles are rendered instead of the correct symbols.

Note that a maui Label can properly display the text.

We’ve encountered an issue related to the inner DataGrid within an outer DataGrid’s RowDetailsTemplate:

Steps to reproduce:

1. Create a DataGrid with editable cells and row details.
2. Inside the RowDetailsTemplate, place a layout (e.g., Grid).
3. Within this layout, embed another DataGrid with editable cells.
4. Start the application and expand row details on the Android platform.
5. Double-tap on any inner DataGrid's cell to open the cell editor. 

At this moment the UI appears unresponsive.

Provide support for nested properties with null values. 

Currently when using the following scenario: null ref exception is throw, when manager is null:

private Person _manager;
public Person Manager
{
    get { return _manager; }
    set { UpdateValue(ref _manager, value); }
}

<telerik:DataGridTextColumn PropertyName="Manager.Name" 
                            HeaderText="Manager"/>

Provide support for null values when nested properties are used in datagrid columns.

Header Text, group header text, do not display some languages characters like Chinese, Thai, etc.

The root reason for this is the fact that the Skia APIs used to draw the text does not support automatic character fallback.

Workaround:

for header text:

<telerik:DataGridTextColumn.HeaderContentTemplate>
    <DataTemplate>
        <Label Text="your text"></Label>
    </DataTemplate>
</telerik:DataGridTextColumn.HeaderContentTemplate>

group header text

<telerik:RadDataGrid.GroupHeaderTemplate>
        <DataTemplate>
            <Label Text="{Binding Group.Key}"/>
        </DataTemplate>
</telerik:RadDataGrid.GroupHeaderTemplate>

column:

<telerik:DataGridTextColumn HeaderText="Name" >
    <telerik:DataGridTextColumn.CellContentTemplate>
        <DataTemplate>
            <Label Text="{Binding Name}"/>
        </DataTemplate>
    </telerik:DataGridTextColumn.CellContentTemplate>
</telerik:DataGridTextColumn>

The DataGrid Search As You Type feature provides search text highlighting through the CellContentStyle property of the columns.  

CellContentStyle is taken into account only for the default columns, so when you specify a custom CellContentTemplate or use a TemplateColumn currently the search text highlighting is not applied.