As a result of an EF Core issue, the ToDataSourceResult() is not able to perform the query when the DataSourceRequest object contains grouping.

The problem occurs using the query below, assembled by Telerik routine:

var temp = _db.Pessoa
    .OrderBy(item => item.Email)
    .Skip(0)
    .Take(40)
    .GroupBy(item => item.Email)
    .OrderBy(g => g.Key)
    .Select(g => new AggregateFunctionsGroup
    {
        Key = g.Key,
        ItemCount = g.Count(),
        HasSubgroups = false,
        Member = "Email",
        AggregateFunctionsProjection = new
        {
            Count_Referencia = _db.Pessoa
                    .Select(t => new
                    {
                        t.IdPessoa,
                        t.Referencia,
                        t.Nome_RazaoSocial,
                        t.Apelido_Fantasia,
                        t.CPF_CNPJ,
                        t.RG_IE,
                        t.Email
                    })
                    .OrderBy(item => item.Email)
                    .Where(item => item.Email == g.Key)
                    .Count()
        },
        Items = g
    })
    .ToList();

In the routine where the AggregateFunctionsGroup is created, the Items property must not only be the query itself, but also the fields specified in the main Select. Or, the call to the Select() method must simply be added:

var temp = _db.Pessoa
    .OrderBy(item => item.Email)
    .Skip(0)
    .Take(40)
    .GroupBy(item => item.Email)
    .OrderBy(g => g.Key)
    .Select(g => new AggregateFunctionsGroup
    {
        Key = g.Key,
        ItemCount = g.Count(),
        HasSubgroups = false,
        Member = "Email",
        AggregateFunctionsProjection = new
        {
            Count_Referencia = _db.Pessoa
                    .Select(t => new
                    {
                        t.IdPessoa,
                        ...
                    })
                    .OrderBy(item => item.Email)
                    .Where(item => item.Email == g.Key)
                    .Count()
        },
        Items = g.Select(t => new
        {
            t.IdPessoa,
            ...
        })
    })
    .ToList();

This way, the issue does not occur.

Currently, the text in the Grid commands can be customized in Kendo UI for jQuery using the following commands:

• https://www.telerik.com/kendo-jquery-ui/documentation/api/javascript/ui/grid/configuration/messages.commands

However, such options are missing in the wrappers. Thus, to customize the texts of the commands in the edit dialog, the elements must be modifed as in the example below:

 function onEdit(e){
      e.container.closest('.k-window').find('.k-window-title').text('My custom text')
      e.container.closest('.k-window').find('.k-button[ref-update-button]').text('Button Update Changed');
      e.container.closest('.k-window').find('.k-button[ref-cancel-button]').text('Button Cancel Changed');
 }

In addition, it will be good to have an option that will allow customizing the Edit Dialog text

Bug report

Even if a message file is added, the command buttons and the popup title in the Grid are not localized

Reproduction of the problem

1. Open the Dojo examples:

• Dojo with messages file - https://dojo.telerik.com/CehWjRrE
• Dojo with overriding the kendo.ui.Grid.prototype.options.messages - https://dojo.telerik.com/RWCxqxIm

2. Decrease the size of the screen so the Grid to be displayed in adaptive mode.
3. Click on a row and select the 'Edit' button to open the Edit popup

Current behavior

The command buttons and the dialog title are not localized:

Expected/desired behavior

It should be possible to change and localize the messages texts.

Workaround

 function onEdit(e){
      e.container.closest('.k-window').find('.k-window-title').text('My custom text')
      e.container.closest('.k-window').find('.k-button[ref-update-button]').text('Button Update Changed');
      e.container.closest('.k-window').find('.k-button[ref-cancel-button]').text('Button Cancel Changed');
 }

Environment

• Kendo UI version: 2025.4.1217
• Browser: [all ]

### Bug report

When subscribing to the "requestStart"/"requestEnd" events of the DataSource after the Grid's initialization, the events do not fire during the Excel export.

### Reproduction of the problem

1. Enable the server operations of the Grid's DataSource.

2. Get a reference to the Grid and handle the DataSource "requestStart"/"requestEnd" events by using the bind() method.

3. Export the Grid's data to Excel through the built-in command.

4. The "requestStart"/"requestEnd" events do not trigger when the read request is activated.

A Dojo sample for reproduction: https://dojo.telerik.com/eyiDIGeM

### Expected/desired behavior

The  "requestStart"/"requestEnd" events must trigger when exporting the Grid to Excel.

### Environment

* **Kendo UI version: 2024.3.806
* **jQuery version: 3.7.0
* **Browser: all

Currently, the DatePicker can be set to read-only mode by adding the "readonly" attribute through the HtmlAttributes() option or by calling the client-side readonly() method.

Is it possible to implement a built-in Readonly() option, so the DatePicker is initialized as read-only? For example:

@(Html.Kendo().DatePickerFor(m => m.StratDate)
  .Readonly(true)
)

### Bug report

On mobile devices, when the TaskBoard columns are filled with cards, the users have trouble scrolling horizontally through the columns. When they attempt to scroll the screen, they accidentally drag cards instead of scrolling the columns. This makes navigation in the TaskBoard quite difficult, particularly for projects with a large number of cards.

### Reproduction of the problem

1. Create a TaskBoard with at least two columns.

2. Fill the columns with cards.

3. Open the browser DevTools and switch to mobile view. Tap a card to scroll the columns horizontally or tap at the bottom of the TaskBoard to activate the horizontal scrollbar.

4. The last card is accidentally dragged.

A Dojo sample for reproduction: https://dojo.telerik.com/izASODan

### Expected/desired behavior

When the user makes a hold/long press/long tap, show the "indicator for drag and drop" and then he/she continues with the gesture by moving the card to the desired column and lift the finger. This way, the accidental dragging will be prevented. For more information, refer to the GitHub issue.

Note: The cards in the TileLayout can be dragged only through the card's title element. The TaskBoard cards can be dragged through the card's body, as well.

### Environment

* **Kendo UI version: 2024.3.806
* **jQuery version: 3.7.0
* **Browser: [all]

Consider the use of TextWriter async methods for the HTML Helpers, for example the WriteInitializationScript methods.  In certain scenarios the use of the synchronous methods causes an exception: System.InvalidOperationException: Synchronous operations are disallowed. Call WriteAsync or set AllowSynchronousIO to true instead.

This can be resolved by explicitly enabling synchronous operations

services.Configure<IISServerOptions>(options =>
    {
        options.AllowSynchronousIO = true;
    });

though synchronous operations have been disabled by default at framework level as of .NET 3.0.

According the the documentation a user should be able to use the keyboard to navigate out of the spreadsheet as deescribed here. However, this does not happen.

Steps to reproduce:

1. Open the Dojo - https://dojo.telerik.com/IvdWHNwo/2
2. Navigate or click in the last cell in the last row
3. Click Tab key.

Current behavior: The focus remains in the same cell.

Expected behavior: Teh second input should be focused.

The issue is a regression starting with version 2024.4.1112

### Bug report

When the virtualization is enabled, in some cases, the selected options in the dropdown do not match the selected options in the input. 

### Reproduction of the problem

1) Create a MultiSelect with Virtualization (for example, the same configuration as in the online demo).

2) Select multiple options from the dropdown.

3) Enter a search entry in the input to filter the displayed options and select a specified option.

4) Scroll down and select another option.

5) Remove some of the already selected options through the input.

6) Open again the dropdown. The selected options in the input do not match the selected options in the dropdown.

A screencast for reproduction: https://app.screencast.com/v6GtyST0dQAnh

### Expected/desired behavior

The FormItemBuilder exposes an EditorTemplateView method which allows a view to represent the item and provides the entire modal to the view.

As the elements available to forms are limited to those hard coded by Telerik and whilst extension methods can be employed to expand this limitation slightly, the ability to create a context specific view would be ideal

The current implementation looks like this

Html.Kendo().Form<Model>()
    .Items(items =>
    {
        items.AddGroup("Test", 1, 10)
            .Items(i =>
                {
                    i.Add().Field(x => x.Username)
                    i.Add().Field(x => x.Password).EditorTemplateView(Html.Partial("MyView"))
                }
            );
    })

In this example, the entire model is provided into MyView. 

I suggest adding an EditorTemplateFor that uses the lamda expression provided in the Field() method such as

Html.Kendo().Form<Model>()
    .Items(items =>
    {
        items.AddGroup("Test", 1, 10)
            .Items(i =>
                {
                    i.Add().Field(x => x.Username)
                    i.Add().Field(x => x.Password).EditorTemplateViewFor(Html.Partial("MyView"))
                }
            );
    })

Bug report

When a user creates a filter with a date, it starts as an empty Datepicker, but the value is appearing as an empty string. Thus, if the user clicks apply, an error appears in the console. If you place a value in the DatePicker and clear it, the value will be Null.

Reproduction of the problem

1. Go to this Progress Telerik ASP.NET Core REPL.
2. Add filter for a Date but keep the datepicker empty.
3. Select apply.
4. Now, add a date and clear the value.

Current behavior

The filter menu sends isnull filter queries in the following format:

While the Filter component sends it as follows:

As a result the ToDataSourceResult method fails.

Expected/desired behavior

If the DatePicker is empty, the filter should properly perform the 'isnull' query upon clicking apply.

Environment

• Kendo UI version: 2023.2.606
• jQuery version: All Supported Versions
• Browser: all

### Bug report

When setting autoWidth: true and expanding a node, the popup's width is not adjusted based on the displayed child nodes.

### Reproduction of the problem

1) Enable the autoWidth option and open the DropDownTree.

2) Expand an item. A horizontal scrollbar appears and the width of the popup is not adjusted as expected:

A Dojo sample for reproduction: https://dojo.telerik.com/faeuFFwb/2

### Expected/desired behavior

The width of the popup must be automatically adjusted when expanding an option and the "autoWidth" option is enabled.

### Environment

* **Kendo UI version: 2025.2.702
* **jQuery version: 3.7.1
* **Browser: [all]

Currently, if a PDFViewer is opened on a mobile device and we use two fingers to zoom its content, the file is zoomed but the more we zoom it, the blurrier its content becomes. The reason for this is the fact that when we use "pinch-zoom" to zoom the PDF file(in a PDFViewer) it is zoomed using the browser's zoom functionality and not the functionality provided by the PDFViewer component. 

It will be a very useful feature if the built-in PDFViewer zoom functionality is used when the user zooms content with two fingers, on a mobile device

The MCP assistant server currently supports Visual Studio, Visual Studio Code and Cursor.

Provide official support for Claude Code as well:

Bug report

When the user searches for a value in the MultiSelect and then selects an item, the search value persists.

Reproduction of the problem

1. Open the Dojo - https://dojo.telerik.com/iUvrZpNm
2. Type something (for example: 'se') in the MultiSelect and select an item

Current behavior

Even when an item is selected, the search value still appears

Expected/desired behavior

When selection is performed, the search value should be cleared

The issue is a regression starting with 2025.4.1321

Workaround:

   select: function (e) {
            e.sender.input.val("");
    },

Dojo - https://dojo.telerik.com/JCwOdXsL

Environment

• Kendo UI version: 2025.4.1321
• Browser: [all ]

Bug report

Regression introduced with 2025 Q3

TabStrip with DOM DataSource rendering does not update contentUrls when updated through the options

Reproduction of the problem

1. Open the following Telerik REPL
2. Navigate to the Script.js tab
3. Notice that the options are explicitly changed.
4. Click on the second tab.
5. Notice that the content remains unchanged.

Current behavior

TabStrip with DOM DataSource rendering does not update contentUrls when updated through the options.

Expected/desired behavior

TabStrip with DOM DataSource rendering should update contentUrls when updated through the options.

Workaround

<script>
   $(() => {
      const tabStrip = $("#tabstrip").data("kendoTabStrip");
      tabStrip._contentUrls[1] = `~/shared/web/tabstrip/ajax/ajaxcontent1.html`;
  });
</script>

Environment

• Kendo UI version: 2025.4.1217
• Browser: [all]

Bug report

When applying data validation to all cells of a xlsx file and trying to import the file via Telerik.Web.Spreadsheet as demonstrated in the Server Import/Export demo the application will crash.

Reproduction of the problem

1. Check ticket 1661158 for a sample xlsx file.
   N.B. The sample file has an AnyValidation rule applied to all cells and a title set for the cells. In addition two columns have predefined styling rules - font, fontSize, etc.
2. Try to load the file using Telerik.Web.Spreadsheet, as demonstrated in the Demo.

Current behavior

Loading will fail.

Expected/desired behavior

File should be loaded

Possibly related to #4017
In the reported scenario there are 1048576 rows, with 16384 columns, resulting in 17179869184 cells all with applied non-default validation value, and we iterate them all to set the validation value, so it can be serialized.

Environment

• Kendo UI version: 2024.3.806