Using the latest 2026.3.811 version produces the following errors:

• kendo.all.d.ts(12072,26): error TS2552: Build:Cannot find name 'SchedulerKendoKeydownEvent'. Did you mean 'SliderKendoKeydownEvent'?
• kendo.all.d.ts(14372,9): error TS2416: Build:Property 'options' in type 'ToggleButton' is not assignable to the same property in base type 'Button'.
• kendo.all.d.ts(14384,15): error TS2430: Build:Interface 'ToggleButtonOptions' incorrectly extends interface 'ButtonOptions'.

Bug report

When a custom bundle is created the kendo.aspnetmvc script is not placed on the correct order. Thus, in some scenarios errors occur. For example if a custom kendo script is created using the following kendo-config.json and MultiColumnComboBox is used with ServerFiltering enabled and error will be thrown:

{
  "version": "2026.2.520",
  "components": [
    {
      "file": "kendo.aspnetmvc.js",
      "features": []
    },       
    {
      "file": "kendo.dropdownlist.js",
      "features": []
    },
    {
      "file": "kendo.multicolumncombobox.js",
      "features": []
    }
  ]
}

Reproduction of the problem

1. Run the attached sample. In the sample a custom bundle as explained above is used. TelerikAspNetCoreApp1.zip
2. Try to select values in the DropDownList or MultiColumnCombobox

Current behavior

The bundle builder allows kendo.aspnetmvc.js to run before the widgets whose UI for ASP.NET Core helpers it augments. The data in the components is not filtered and the following error is thrown:

Uncaught TypeError: kendo.ui.MultiColumnComboBox.requestData is not a function

Expected/desired behavior

The kendo.aspnetmvc.js schould be ordered correctly by the custom script builder, so errors to be avoided and the components to work as expected.

TicketID:

1716198

Environment

• Kendo/Telerik version: 2026.2.520
• Browser: [all ]

Bug report

Editor components throw AmbiguousMatchException when bound with models that have property shadowing in inheritance hierarchies.

Reproduction of the problem

1. Create a model hierarchy where a derived class shadows a base class property with new keyword
2. Bind the Editor component with the shadowed property
3. Exception is thrown during reflection

Current behavior

(optional)
The components should handle property shadowing gracefully and generate the appropriate HTML input element.

Expected/desired behavior

AmbiguousMatchException is thrown when trying to bind the component to the shadowed property.

TicketID:

1699473

Environment

• Kendo UI version: 2025.3.825
• Browser: [all]

I am working on a grid that has 3 requirements that seem to cause the bug:

• A FK column must have its lookup values loaded remotely
• The grid has sticky columns
• The grid is loaded inside a tab strip control

The combination of these 3 factors causes the grid not to load and results in a devtools console error. It's worth noting that removing any of the 3 bullet points above (e.g. NOT using sticky columns, NOT loading grid in tab control, or NOT have a remote FK column) allows the grid to load properly.

The error thrown in the DevTools console indicates that the grid's "tbody" property is not created at the time it is trying to call _setStickyStyles.

Before error is thrown (mouse is hovering over "tbody" property):

After error is thrown (look at console output):

I have upload a zip file containing a sample project that demonstrates the issue. When you launch the sample application, there are 2 links at the top of the page, "No Tabs" and "Tabs". The issue is reproducible on the "Tabs" page. Both pages use the same grid partial, but the "Tabs" page loads the partial through the tabstrip with a controller action. The "Tabs" page includes the 3 bullet points I indicated above that cause the problem.

The workaround I am using for now in my application is to NOT set the columns as sticky in my partial view. Instead, I set the sticky columns using the grid's API method "stickColumn" (https://www.telerik.com/kendo-jquery-ui/documentation/api/javascript/ui/grid/methods/stickcolumn) during the grid's dataBinding event (to ensure sticky columns are set AFTER grid initialization). This allows the grid to load and sets the sticky columns appropriately.

Thank you!

### Bug report

When building the scripts with NPM, there is syntax error "Unexpected number":

### Reproduction of the problem

Build the scripts (version 2025.3.812).

### Expected/desired behavior

The scripts must be built successfully.

### Workaround:

Remove the extra single quotes that wrap the version in the "rollup.mjs.config.mjs" and "rollup.modules.config.js" files:

• rollup.mjs.config.mjs

import glob from 'glob';
import path from 'path';
import { nodeResolve } from '@rollup/plugin-node-resolve';
import polyfill from 'rollup-plugin-polyfill';
import alias from '@rollup/plugin-alias';

...

const version = '2025.3.812';

• rollup.modules.config.mjs

import glob from "glob";
import path from "path";
import { nodeResolve } from "@rollup/plugin-node-resolve";
import polyfill from "rollup-plugin-polyfill";
import alias from "@rollup/plugin-alias";

...

const version = '2025.3.812';

### Environment

* **Kendo UI version: 2025.3.812

As stated in the title, the Save() action of a grid (with pagination, not endless scroll) does set the scroll position to the top instead of persisting it. 

I tried to follow instructions from https://www.telerik.com/aspnet-core-ui/documentation/html-helpers/data-management/grid/scrolling/overview#restoring-the-scroll-position but without success. The scroll position is moved to the top after the DataBound event handler.

Hi Team,

Currently, Telerik.Licensing NuGet package only has target for netstandard2.0, netframework462 and net6.0. I cannot use .NET 6 for my .NET 9 application because .NET 6 is out of support. 

This is a feature request to either

• Remove the net6.0 TFM and reply only on netstandard2.0
  • or
• Add net8.0 and net9.0 targets.

Thank you,

Arthur

Bug report

When enabling Editing for the Grid or TreeList a "No License" overlay is displayed in the following scenarios:

Reproduction of the problem

• Grid: overlay is displayed on load

@(Html.Kendo().Grid<TelerikMvcApp13.Models.OrderViewModel>()
    .Name("grid")
    .Columns(columns =>
    {
        columns.Bound(p => p.OrderID).Filterable(false);
        columns.Bound(p => p.Freight);
        columns.Bound(p => p.OrderDate).Format("{0:MM/dd/yyyy}");
        columns.Bound(p => p.ShipName);
        columns.Bound(p => p.ShipCity);
        columns.Command(c => c.Edit());
    })
    .Editable(e=>e.Mode(GridEditMode.PopUp))
    .Pageable()
    .Sortable()
    .Scrollable()
    .Filterable()
    .DataSource(dataSource => dataSource
        .Ajax()
        .PageSize(20)
        .Model(m=>m.Id(o=>o.OrderID))
        .Read(read => read.Action("Orders_Read", "Grid"))
        .Update(read => read.Action("Orders_Update", "Grid"))
        .Create(read => read.Action("Orders_Create", "Grid"))
        .Destroy(read => read.Action("Orders_Destroy", "Grid"))
    )
)

• TreeList: initially there is no overlay. Clicking on "Edit" button shows overlay and "No License" popup.

@(Html.Kendo().TreeList<Kendo.Mvc.Examples.Models.TreeList.EmployeeDirectoryModelPopUp>()
    .Name("treelist")
    .Toolbar(toolbar => toolbar.Create())
    .Columns(columns =>
    {
        columns.Add().Field(e => e.FirstName).Width(220).Title("First Name");
        columns.Add().Field(e => e.LastName).Width(100).Title("Last Name");
        columns.Add().Field(e => e.Position);
        columns.Add().Field(e => e.HireDate).Format("{0:MMMM d, yyyy}");
        columns.Add().Field(e => e.Phone).Width(200);
        columns.Add().Field(e => e.Extension).Width(140).Title("Ext").Format("{0:#}");
        columns.Add().Width(300).Command(c =>
        {
            c.CreateChild().Text("Add child");
            c.Edit();
            c.Destroy();
        });
    })
    .Editable(e => e.Mode("popup"))
    .DataSource(dataSource => dataSource
        .Create(create => create.Action("Create", "EmployeeDirectory"))
        .Read(read => read.Action("All", "EmployeeDirectory"))
        .Update(update => update.Action("Update", "EmployeeDirectory"))
        .Destroy(delete => delete.Action("Destroy", "EmployeeDirectory"))
        .Model(m =>
        {
            m.Id(f => f.EmployeeId);
            m.ParentId(f => f.ReportsTo);
            m.Expanded(true);
            m.Field(f => f.FirstName);
            m.Field(f => f.LastName);
            m.Field(f => f.ReportsTo);
            m.Field(f => f.HireDate);
            m.Field(f => f.Extension).DefaultValue(0);
            m.Field(f => f.Position);
        })
    )
    .Height(540)
)

Expected/desired behavior

No overlay and popup should be displayed in case of valid license.

TicketID:

(optional)
Provide the TicketID, where the bug report initiated.

Environment

• Kendo UI version: 2025.1.211

Bug Report

The Pickers are not bound to model value when a nullable DateTime is set.

Reproduction of the problem

1. Create a model with a nullable DateTime property

        public class MyModel
        {
              public DateTime? Birthday { get; set; }
        }
   

2. Declare either a DatePickerFor, DateRangePickerFor, DateInputFor, or TimePickerFor Helpers

       @(Html.Kendo().TimePickerFor(m => m.Birthday))
   

3. Notice, that the value has not been bound accordingly.

Current behavior

The Pickers are not bound to model value when nullable.

Expected behavior

The Pickers are not bound to model value when a nullable DateTime is set.

Environment

Kendo UI version: 2024.4.1112
jQuery version: x.y
Browser: [all]

### Bug report

When building the scripts through the 'npx gulp scripts' command, there is an error "Error: Cannot find module './build/gulp/kendo-version'".

### Reproduction of the problem

Download any of the source bundles (Core, MVC, jQuery) and try to build the scripts.

### Environment

* **Kendo UI version: 2024.4.1112

Overview

Currently, the Telerik UI for ASP.NET Core DataSource does not expose a Deferred() API configuration. In comparison to its Telerik UI for ASP.NET MVC counterpart.

It would be beneficial to expose the ability to defer the component in the following manner:

@(Html.Kendo().DataSource<TelerikMvcApp119.Models.OrderViewModel>()
    .Name("ds")
    .Ajax(dataSource => dataSource
		.Read(read => read.Action("AssetType_Read", "AssetTypes"))
	)
    .Deferred()
)

It will also enable users to employ CSP using a granular deferred initialization into a separate script tag. Annotated with the nonce attribute

Current behavior

The Telerik UI for ASP.NET Core DataSource does not expose a built-in configuration for deferring the DataSource.

Expected/desired behavior

The Telerik UI for ASP.NET Core DataSource should expose a built-in configuration for deferring the DataSource.

Environment

• Kendo UI version: 2024.2.514
• Browser: [all]

Bug report

TabStrip is not CSP compliant when the Selected() API configuration is enabled.

Reproduction of the problem

1. Create an application with CSP headers
2. Create a TabStrip and set the Selected() API configuration for one of the items

@(Html.Kendo().TabStrip()
    .Name("tabstrip")
    .Items(items =>
    {
        items.Add().Text("Details")
		.Selected(true)
		.LoadContentFrom("Details", "Home", Model);
    
    })
)

Current behavior

Setting the Select() API configuration will lead to the following Content Security Policy Header Report Error.

Refused to apply inline style because it violates the following Content Security Policy directive: "default-src 'self'". Note that 'style-src' was not explicitly set, so 'default-src' is used as a fallback.

Expected/desired behavior

Setting the Select() API configuration should not lead to a Content Security Policy Header Report Error.

Environment

• Kendo UI version: 2024.2.514
• Browser: [all]

Bug report

When the Columns.Command.Edit.UpdateText property is set to Update, the text will not be modified and will remain as the default value Save.

Reproduction of the problem

@(Html.Kendo().Grid<Kendo.Mvc.Examples.Models.ProductViewModel>()
    .Name("grid")
    .Columns(columns =>
    {
        columns.Command(command => { 
            command.Edit().UpdateText("Update");  //Will not work
        }).Width(250);
    })
    //....
)

REPL
https://netcorerepl.telerik.com/wIuyvtcO41rAa82G36

Expected/desired behavior

The text should change to the specified content within UpdateText.

Workaround

Set the text via JavaScript using the setOptions method and columns.command.text:

        $(document).ready(function(){
            var grid = $("#grid").data("kendoGrid");
            var options = grid.getOptions();
            //set the text for the first command in the last column
            // as shown in the second example on:
            //https://docs.telerik.com/kendo-ui/api/javascript/ui/grid/configuration/columns.command#columnscommandtext
            options.columns[4].command[0].text = { edit: "Edit", update: "Update" };
            grid.setOptions(options);
        });

REPL
https://netcorerepl.telerik.com/wIYeGmOz39LL8mHN26

Environment

• Kendo UI version: 2024.1.319
• jQuery version: Related Supported Versions
• Browser: all

At this stage, the Serialize() method depends on Newtonsoft.Json:

using Newtonsoft.Json;

namespace Kendo.Mvc.Infrastructure
{
    public class DefaultJavaScriptSerializer : IJavaScriptSerializer
    {
        public string Serialize(object value)
        {
            return JsonConvert.SerializeObject(value).Replace(@"<", @"\u003c").Replace(@">", @"\u003e");
        }
    }
}

Is it possible to remove the dependency and use the System.Text.Json serializer instead?

### Bug report

When the deferred scripts are created, the script source points at the root of the application instead of the application's root directory.

### Reproduction of the problem

Enable the global deferred initialization and call the @(Html.Kendo().DeferredScriptFile()) method.

The rendered script tag is:  <script src="/kendo-deferred-scripts-XXXX.js"></script>

But it must be: <script src="/MyWebsite/kendo-deferred-scripts-XXXX.js"></script>

### Solution:

If you add a tilde in the Url.Content(), the generated script file must be located as expected:

public HtmlString DeferredScriptFile(string nonce = "")
{
           ...
            var scriptResult= hasDeferredScritps ? $@"<script src=""{urlHelper.Content("~/kendo-deferred-scripts-" + guid + ".js")}"" {(string.IsNullOrEmpty(nonce) ? "" : "nonce=" + '"' + nonce + '"')}></script>" : "";
            var styleResult = hasDeferredStyles ? $@"<link href=""{urlHelper.Content("~/kendo-deferred-styles-" + guid + ".css")}"" {(string.IsNullOrEmpty(nonce) ? "" : "nonce=" + '"' + nonce + '"')} rel=""stylesheet""></link>" : "";
            return new HtmlString(scriptResult + System.Environment.NewLine + styleResult);
}

### Environment

* **Telerik UI for ASP.NET Core version: 2023.3.1114
* **Browser:** [all]

### Bug report

When the Dialog is configured with actions and the Content Security Policy is enabled, it throws an "Invalid template" error.

### Reproduction of the problem

1) Configure a Dialog widget with actions and set the CSP with the following content:

<meta http-equiv="Content-Security-Policy" content="script-src 'self' 'unsafe-inline' https://kendo.cdn.telerik.com https://code.jquery.com; style-src 'self' 'unsafe-inline' https://kendo.cdn.telerik.com;" />

2) Open the browser console to review the error.

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

### Expected/desired behavior

The Dialog should be rendered correctly without using the 'unsafe-eval' keyword in the "script-src" directive.

### Workaround

Insert the following script before the Dialog initialization:

 <script>
    kendo.ui.Dialog.fn._mergeTextWithOptions = function(action) { var text = action.text; if(text) { return kendo.isFunction(text) ? text(this.options) : text; } return ""; }
</script>

### Environment

* **Kendo UI version: 2023.2.606
* **jQuery version: 3.4.1
* **Browser: [all]

Hi,

https://netcorerepl.telerik.com/?_gl=1*ptwrwx*_ga*MTM4MzE0OTY5MC4xNjczNDQ5ODc1*_ga_9JSNBCSF54*MTY3NzE1MzU1Ny44MC4xLjE2NzcxNTg0NTEuNjAuMC4w

From: Edit in Telerik REPL

https://demos.telerik.com/aspnet-core/gantt

Results:

One or more compilation failures occurred: /Views/Snippet.cshtml(24,18): Error RZ1006: The section block is missing a closing "}" character. Make sure you have a matching "}" character for all the "{" characters within this block, and that none of the "}" characters are being interpreted as markup.

Thanks

Andreas

The 'footer' attribute in the TagHelpers for both the DatePicker and DateTimePicker does not result in any corresponding markup / Javascript configuration on the page created by the view.

See https://netcorerepl.telerik.com/QxaPwpPt57ypaI4307