Unplanned
Last Updated: 01 Oct 2026 11:01 by David

Bug report

Reproduction of the problem

(bug report only)
The label of the filter menu icon displays: “column filter menu settings”. In version 12.0.0 it included the name of the column field.

1. Run this example: https://blazorrepl.telerik.com/cKFaOPvO56rcaHqx16
2. Hover a filter icon in the Grid’s header with the mouse cursor.

Current behavior

(optional)
The label “column filter menu settings” appears.

Expected/desired behavior

The label text includes the column name, e.g., “Price column filter menu settings”.

Workaround:

https://blazorrepl.telerik.com/cUPYaPlO55EJNiKJ24

Environment

  • Kendo/Telerik version: 15.0.1
  • Browser: [all]
Unplanned
Last Updated: 23 Sep 2026 10:00 by ADMIN
In a Grid with multiple columns and InCell editing, rapid tab (quick tab key presses) eventually "jumps" the focus out of the Grid, leaves behind a cell open for editing and instead focuses another UI element on the page.
Unplanned
Last Updated: 23 Sep 2026 09:59 by ADMIN

Hello,

When a Grid is using multi column headers, and I add one more column in the OnBeforeExport event, this new column has no title in the exported file.

A possible workaround might be to use a column with zero Width and change the width in OnBeforeExport.

@using Telerik.Blazor.Common.Export.Excel
@using Telerik.Blazor.Components.Grid

<TelerikGrid TItem="@FlowRun"
             Pageable="true"
             OnRead="@GetData">

    <GridToolBar>
        <GridCommandButton Command="ExcelExport" Icon="file-excel">Export to Excel</GridCommandButton>
        <GridCommandButton Command="CsvExport" Icon="file-csv">Export to CSV</GridCommandButton>
        <label class="k-checkbox-label"><TelerikCheckBox @bind-Value="@ExportAllPages" />Export All Pages</label>
    </GridToolBar>

    <GridExport>
        <GridExcelExport FileName="telerik-grid-export" AllPages="@ExportAllPages" OnBeforeExport="@BeforeExcelExport" />
        <GridCsvExport FileName="telerik-grid-export" AllPages="@ExportAllPages" OnBeforeExport="@BeforeCsvExport" />
    </GridExport>

    <GridColumns>
        <GridColumn Field="@nameof(FlowRun.FileName)" Title="File Name" Width="300px" />
        <GridColumn Field="@nameof(FlowRun.Type)" Title="Type" Width="100px" />
        <GridColumn Field="@nameof(FlowRun.FileSize)" Title="File Size" Width="200px" />
        <GridColumn Title="Source">
            <Columns>
                <GridColumn Field="@(nameof(FlowRun.Source))" Title="MPID"/>
                <GridColumn Field="@(nameof(FlowRun.SourceFileProtocol))" Title="Type" />
            </Columns>
        </GridColumn>
        <GridColumn Field="@nameof(FlowRun.ErrorMessage)"
                    Title = "Error"
                    Width="0" />
    </GridColumns>
</TelerikGrid>

@code {
    bool ExportAllPages { get; set; }

    private async Task GetData(GridReadEventArgs args)
    {
        args.Data = Enumerable.Range(1, 10).Select(x => new FlowRun
            {
                FileName = $"File {x}",
                Type = $"Type {x}",
                FileSize = x * 2,
                Source = $"Source {x}",
                SourceFileProtocol = FileProtocol.CIX,
                ErrorMessage = $"Error {x}"
            }).ToList();

        args.Total = 100;
    }

    private void BeforeCsvExport(GridBeforeCsvExportEventArgs obj)
    {
        AddErrorMessageColumn(obj);
    }

    private void BeforeExcelExport(GridBeforeExcelExportEventArgs obj)
    {
        AddErrorMessageColumn(obj);
    }

    private void AddErrorMessageColumn(GridBeforeSpreadsheetExportEventArgs args)
    {
        args.Columns.Find(x => x.Field == nameof(FlowRun.ErrorMessage)).Width = "100px";

        //args.Columns.Add(new ExcelExportableColumn
        //{            
        //    Field = nameof(FlowRun.ErrorMessage),
        //    Title = "Error"
        //});
    }

    public class FlowRun
    {
        public string FileName { get; set; }
        public string Type { get; set; }
        public long? FileSize { get; set; }
        public string Source { get; set; }
        public FileProtocol SourceFileProtocol { get; set; }
        public string ErrorMessage { get; set; }
    }

    public enum FileProtocol
    {
        Unknown,
        PIX,
        CIX,
        SS
    }
}

Unplanned
Last Updated: 23 Sep 2026 09:58 by ADMIN

I have a Telerik Pager within a Telerik Grid. If I select a larger page size within the pager, then select a smaller size and do not scroll, the next time I open the pager, the dropdown portion opens in the wrong place. When I view the inspect tool, it appears that the CSS top value is not being updated when changing page sizes from bigger to smaller. Is this a Telerik limitation with the pager?
In the images, we select items per page from 10 to 25, and then we go immediately from 25 to 10 items per page. Without scrolling, we click into the drop down list again and we are able to replicate this issue.

Before: Items per page:     10 -> 25



After:    


Thank you in advance.

Unplanned
Last Updated: 23 Sep 2026 09:57 by ADMIN

When the Grid is grouped and aggregate functions are enabled, paging performance degrades significantly because grouping and aggregate calculations are executed on every page change. This results in noticeable delays and UI stutter, especially in WebAssembly applications and larger datasets.

This enhancement optimizes page navigation for grouped Grid scenarios with aggregates by avoiding repeated processing when the underlying data has not changed, resulting in substantially faster paging performance while preserving existing functionality and first-load behavior.

Unplanned
Last Updated: 15 Sep 2026 11:57 by Markus
Created by: Markus
Comments: 0
Category: Grid
Type: Bug Report
2

To optimize performance, I built a custom component that allows the user to choose which aggregates should be calculated. This component ensures that <GridAggregate> tags are inserted into <GridAggregates> via a foreach loop.

This works without any issues, at least when the selection is made for the first time. 

However, if a selection is made in which the column of a new aggregate appears before an already selected aggregate, errors occur in the grid. AggregateResults now contains duplicates of an existing aggregate, and the new aggregates are missing.

Test project available in ticket 1718830.

Unplanned
Last Updated: 15 Sep 2026 09:38 by Matthias
Enable the user to select multiple records, using the shift key, across different pages (scroll downs) when the Grid has virtual scrolling.
Unplanned
Last Updated: 31 Aug 2026 06:15 by ADMIN
When scrolling up in a virtual Grid, the rows "above" are not be kept or loaded like when scrolling down, and it takes a while before they get loaded and shown. This behaviour is not very user friendly and should be corrected.
Unplanned
Last Updated: 19 Aug 2026 14:05 by Oriol

Bug report

Reproduction of the problem

(bug report only)
Run this example: https://blazorrepl.telerik.com/GqaiPtbH54zmCKSH29
There are two editable columns (Price).
1. Click on the first Price column cell in the first row.
2. Press Tab key. The last editable cell on the first row is focused and is brought into view.
3. Press Tab again. The first editable cell on the second row is focused and brought into view.
4. Press Tab again. The last editable cell on the second row is focused, but it is not brought into view.

Current behavior

(optional)

Navigation across editable cells works inconsistently. On every other row, the last editable cell is not brought into view.

Expected/desired behavior

Navigation should work consistently on every row.

Environment

  • Kendo/Telerik version: 15.0.0
  • jQuery version: x.y
  • Browser: [all]
Unplanned
Last Updated: 07 Jul 2026 10:22 by Domingos Portela

The Grid resets and disables the adaptive mode for a column menu if the column has been hidden. The component also uses the previous adaptive mode that is no longer correct if the browser window is resized.

Steps to reproduce:

  • Shrink the browser width. Hide a column, show it back and then show its column menu.
  • Start from a wide browser. Show a column menu. Shrink the browser. Show the same column menu.
  • Start from a narrow browser. Show a column menu. Expand the browser. Show the same column menu.

Test page:

<TelerikGrid Data="@GridData"
             AdaptiveMode="@AdaptiveMode.Auto"
             FilterMode="GridFilterMode.FilterMenu"
             ShowColumnMenu="true">
    <GridColumns>
        <GridColumn Field="@nameof(Product.Name)" />
        <GridColumn Field="@nameof(Product.Group)" />
        <GridColumn Field="@nameof(Product.Price)" DisplayFormat="{0:c2}" />
        <GridColumn Field="@nameof(Product.Quantity)" DisplayFormat="{0:n0}" />
        <GridColumn Field="@nameof(Product.Released)" DisplayFormat="{0:d}" />
        <GridColumn Field="@nameof(Product.Discontinued)" />
    </GridColumns>
</TelerikGrid>

@code {
    private List<Product> GridData { get; set; } = new();

    protected override void OnInitialized()
    {
        var rnd = Random.Shared;

        for (int i = 1; i <= 3; i++)
        {
            GridData.Add(new Product()
            {
                Id = i,
                Name = $"Name {i} {(char)rnd.Next(65, 91)}{(char)rnd.Next(65, 91)}",
                Group = $"Group {i % 3 + 1}",
                Price = rnd.Next(1, 100) * 1.23m,
                Quantity = rnd.Next(0, 10000),
                Released = DateTime.Today.AddDays(-rnd.Next(60, 1000)),
                Discontinued = i % 4 == 0
            });
        }
    }

    public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; } = string.Empty;
        public string Group { get; set; } = string.Empty;
        public decimal Price { get; set; }
        public int Quantity { get; set; }
        public DateTime Released { get; set; }
        public bool Discontinued { get; set; }
    }
}

Unplanned
Last Updated: 07 Jul 2026 07:17 by Sadik

Customers report inconsistent in-cell editing behavior with DatePicker columns in the Grid.

  • Case 1: click a date cell to enter edit mode, then click outside the Grid — edit mode terminates.
  • Case 2: click a date cell to enter edit mode, open the DatePicker popup, then click outside the Grid — the popup closes but the cell remains stuck in edit mode until pressing Esc or clicking another cell.

Here is a REPL test page that reproduces the issue (first date column) and provides a workaround (second date column):

https://blazorrepl.telerik.com/QAErkrEh090ykIxR16

The workaround relies on Grid EditorTemplate, the DatePicker OnClose event, and programmatic Grid edit mode management. The relevant code is:

@using System.ComponentModel.DataAnnotations

<TelerikGrid @ref="@GridRef"
             Data="@GridData"
             EditMode="@GridEditMode.Incell"
             OnUpdate="@OnGridUpdate"
             OnCreate="@OnGridCreate">
    <GridToolBarTemplate>
        <GridCommandButton Command="Add">Add Item</GridCommandButton>
    </GridToolBarTemplate>
    <GridColumns>
        <GridColumn Field="@nameof(Product.Name)" />
        <GridColumn Field="@nameof(Product.StartDate)" Title="BUG" DisplayFormat="{0:d}" />
        <GridColumn Field="@nameof(Product.EndDate)" Title="WORKAROUND" DisplayFormat="{0:d}">
            <EditorTemplate>
                @{ var editItem = (Product)context; }
                <TelerikDatePicker Value="editItem.EndDate"
                                   ValueChanged="@((DateTime? newValue) => OnGridDatePickerValueChanged(newValue, editItem))"
                                   ValueExpression="@( () => editItem.EndDate )"
                                   OnClose="@(async () => await OnGridDatePickerClose(editItem))" />
            </EditorTemplate>
        </GridColumn>
    </GridColumns>
</TelerikGrid>

@code {
    #nullable enable

    private TelerikGrid<Product>? GridRef;
    private List<Product> GridData { get; set; } = new();

    private int LastId { get; set; }

    private DateTime LastDatePickerValueChanged { get; set; } = DateTime.Now;

    private void OnGridDatePickerValueChanged(DateTime? newValue, Product editItem)
    {
        editItem.EndDate = newValue;
        LastDatePickerValueChanged = DateTime.Now;
    }

    private async Task OnGridDatePickerClose(Product editItem)
    {
        if (DateTime.Now - LastDatePickerValueChanged > TimeSpan.FromMilliseconds(500))
        {
            GridState<Product> gridState = GridRef!.GetState();

            if (gridState.EditItem is not null && gridState.EditItem.Id == editItem.Id)
            {
                // Uncomment to perform an item update instead of cancel
                // OnGridUpdate(new GridCommandEventArgs { Item = editItem });

                gridState.OriginalEditItem = null!;
                gridState.EditItem = null!;

                await GridRef.SetStateAsync(gridState);
            }
        }
    }

    private void OnGridCreate(GridCommandEventArgs args)
    {
        var createdItem = (Product)args.Item;

        createdItem.Id = ++LastId;

        GridData.Insert(0, createdItem);
    }

    private void OnGridUpdate(GridCommandEventArgs args)
    {
        var updatedItem = (Product)args.Item;
        var originalItemIndex = GridData.FindIndex(i => i.Id == updatedItem.Id);

        if (originalItemIndex != -1)
        {
            GridData[originalItemIndex] = updatedItem;
        }
    }

    protected override void OnInitialized()
    {
        for (int i = 1; i <= 5; i++)
        {
            GridData.Add(new Product()
            {
                Id = ++LastId,
                Name = $"Product {LastId}",
                Price = Random.Shared.Next(0, 100) * 1.23m,
                Quantity = Random.Shared.Next(0, 1000),
                StartDate = DateTime.Today.AddDays(-Random.Shared.Next(60, 1000)),
                EndDate = DateTime.Today.AddDays(Random.Shared.Next(1, 60)),
                IsActive = LastId % 4 > 0
            });
        }
    }

    public class Product
    {
        public int Id { get; set; }
        [Required]
        public string Name { get; set; } = string.Empty;
        public decimal Price { get; set; }
        public int Quantity { get; set; }
        public DateTime? StartDate { get; set; }
        public DateTime? EndDate { get; set; }
        public bool IsActive { get; set; }
    }
}

Unplanned
Last Updated: 16 Apr 2026 12:10 by Steve
Created by: Steve
Comments: 0
Category: Grid
Type: Bug Report
0

Bug Description

Introduced in v13.1.0. An item that has no text (empty string) renders a span (.k-list-item-text) with height 0px.

Steps to Reproduce

Steps to reproduce the behavior:

  1. Go to https://blazorrepl.telerik.com/mgEobKlm00OJm8OW55
  2. Click the DropDownList to show its list
  3. Inspect the second item in the browser dev tools

Also reproducible in: https://dojo.telerik.com/ZVOXYUsb/3

Expected Behavior

The item that has no text should have the same height as items that have text.

Actual Behavior

The height of the span.k-list-item-text is 0px.

Screenshots/Videos

Environment Information

Affected Theme(s)

  • All themes

Affected Component(s)

Please specify the component(s) where the bug occurs: ___________

Affected Suites

  • Kendo UI for jQuery
  • Telerik UI for Blazor
  • Telerik UI for ASP.NET Core
  • Telerik UI for ASP.NET MVC
  • likely others as well

Browser Information

  • All browsers

Build System Information

Reproduction Case

CodePen/StackBlitz/JSFiddle Link

https://blazorrepl.telerik.com/mgEobKlm00OJm8OW55

https://dojo.telerik.com/ZVOXYUsb/3

Sample Code

<TelerikDropDownList Data="@DropDownListData" @bind-Value="DropDownListValue" />

@code {
    private List<string> DropDownListData = new List<string>() { "Item1", string.Empty, "Item3" };

    private string DropDownListValue { get; set; } = string.Empty;

    protected override void OnInitialized()
    {
        DropDownListValue = string.Empty;
    }
}

Workaround

<style>
    .k-list-item-text {
        min-height: 20px;
    }
</style>

Unplanned
Last Updated: 06 Apr 2026 14:39 by ADMIN

Title: WCAG 1.3.1: Ensures elements with an ARIA role that require child roles contain them (#\39 374a450-079d-4586-b823-d6bc7723505f)
Tags: Accessibility, WCAG 1.3.1, aria-required-children

Issue: Ensures elements with an ARIA role that require child roles contain them (aria-required-children - https://accessibilityinsights.io/info-examples/web/aria-required-children)

Target application: Hermes Home - https://localhost/TrafficLoss

Element path: #\39 374a450-079d-4586-b823-d6bc7723505f

Snippet: <div class="k-grid-aria-root" id="9374a450-079d-4586-b823-d6bc7723505f" role="grid" aria-label="Data table">

How to fix: 
Fix any of the following:
  Element has children which are not allowed (see related nodes)
  Element has no aria-busy="true" attribute

Environment: Microsoft Edge version 111.0.1661.41

====

This accessibility issue was found using Accessibility Insights for Web 2.37.3 (axe-core 4.6.3), a tool that helps find and fix accessibility issues. Get more information & download this tool at http://aka.ms/AccessibilityInsights.

 

============================  code =============================

                           <TelerikGrid Data="@ViewModel.RDLInformation" TItem="TLSummary"
                                                        Pageable="true" 
                                                        Sortable="true" 
                                                        Groupable="false"
                                                        FilterMode="Telerik.Blazor.GridFilterMode.FilterRow"
                                                        Resizable="true" 
                                                        Reorderable="true"
                                                        Height = "100%">

....

                            </TelerikGrid>

Unplanned
Last Updated: 19 Mar 2026 14:46 by Clifton
===TELERIK ADMIN EDIT===

Specifically, if the div mentioned in the error does not have tabindex=1, tabbing from the header causes the browser to focus that area, which is not the expected behavior. Ideally, the focus should move to the first cell, as that intermediate area is not user-interactive.

On the other hand, if tabindex=-1 is used, tools like Аxe and Lighthouse report errors. Removing the tabindex attribute altogether still results in errors, and the browser continues to focus that area.

We are actively exploring possible approaches to address this, but at the moment, there is no immediate solution we can apply without side effects.
Unplanned
Last Updated: 18 Mar 2026 13:09 by ADMIN
During a recent penetration test on our Blazor application that uses Telerik Blazor UI components, a security finding was reported regarding the possibility of Excel macro injection through exported Excel files generated via the Telerik Excel Export feature. 
We would like Telerik to implement built‑in safeguards to automatically neutralize potential macro injection vectors.

The penetration test revealed that it is currently possible to insert values beginning with Excel formula metacharacters—such as =, +, -, and @—into fields that are later exported using Telerik’s Excel Export functionality.
In older versions of Microsoft Excel, these values may be interpreted and executed as formulas when users open the exported file. Even though newer Excel versions often warn users, this still presents a security concern and may violate corporate export or data‑handling policies.

See also this blogpost: https://blog.securelayer7.net/how-to-perform-csv-excel-macro-injection/

The Telerik Excel Export functionality should include an option to automatically sanitize or escape values that may pose a risk of Excel macro or formula injection.
- Automatic escaping of formula-starting characters: Prepend a single quote (') to any exported value beginning with: '=', '+', '-', '@'.
- Optional configuration flag to enable/disable this behavior, for example: <GridExcelExportSettings EscapeFormulas="true" />

While we can implement a workaround in our own application code, we believe this is a security concern that many customers may encounter, and therefore a native solution within the Telerik framework would be highly valuable.

We kindly request that Telerik consider adding a built‑in mechanism to protect against Excel macro injection in exported files. This would improve security, reduce custom development work, and strengthen the reliability of Telerik’s Blazor export functionality.
Unplanned
Last Updated: 18 Mar 2026 08:35 by ADMIN

If LoadGroupsOnDemand="false", I am able to programmatically expand the groups through the state. However, this is not possible when loading group data on demand.

Please allow programmatically expanding the groups when LoadGroupsOnDemand="true". This should go together with an event (OnStateChanged?) that will fire when LOD groups are expanded or collapsed.

Unplanned
Last Updated: 16 Mar 2026 10:49 by ADMIN
Created by: David
Comments: 2
Category: Grid
Type: Feature Request
1

Draft feature request (copy/paste)

Title: Add per-column value converters (WPF-style) to Telerik Blazor Grid columns

Product: UI for Blazor → Grid
Type: Feature Request

Description:
In Telerik UI for WPF, grid column definitions can reference a converter by name (e.g., IValueConverter) to transform values for display without writing a custom cell template for each column.

In Telerik UI for Blazor Grid, templates are currently the primary way to change how values render in a column (which works, but becomes repetitive across many columns/grids).

Request:
Add a column-level conversion API that allows specifying a converter/formatter function for display (and optionally editing). Example concepts:

  • Converter="nameof(MyConverters.StatusToText)"

  • or DisplayConverter="(item) => …" / ValueFormatter="Func<TItem, object, string>"

  • optionally ConvertBack-like support for editing scenarios (or separate EditConverter)

Why this is needed:

  • Reduces repeated <Template> markup for simple formatting/transformations

  • Centralizes formatting/conversion logic in reusable code

  • Improves maintainability and consistency across grids

  • Eases migration for teams coming from Telerik WPF where converters are a common pattern

Use cases:

  • Enum/int → user-friendly text

  • Boolean → “Yes/No”, icons, badges

  • Null/empty → placeholder text

  • Code → display name (via lookup)

  • Domain-specific formatting shared across many grids

Workarounds today:

  • Column <Template> or computed properties (both valid, but not as concise/reusable for large grids)

  • Extracting RenderFragments can reduce repetition, but still requires templating infrastructure for what is logically a simple conversion step

Expected behavior:

  • Converter applies consistently anywhere the column renders (cell, export if applicable, etc.)

  • Works with sorting/filtering in a predictable way (ideally sorting/filtering still uses raw field value unless explicitly configured)


 

Unplanned
Last Updated: 16 Mar 2026 07:31 by Michal
Created by: Michal
Comments: 0
Category: Grid
Type: Feature Request
1
Please expose an Enabled parameter for all built-in GridToolBar tools. When set, the parameter will override the default behavior for the built-in tools that manage their enabled state internally (such as Edit, which enables only when there is a selected row).
Unplanned
Last Updated: 16 Mar 2026 07:28 by Michal
Please expose built-in Grid ToolBar tools like GridToolBarButtonTool and GridToolBarToggleButtonTool that are used for custom actions and have an OnClick handler. Unlike the current custom Grid ToolBar tools, these new built-in tools will be able to show in the Grid ToolBar's overflow menu when the available horizontal space is limited.
Unplanned
Last Updated: 13 Mar 2026 07:42 by ADMIN
Created by: Humayoon
Comments: 4
Category: Grid
Type: Feature Request
17

Hi,

I would like to have a Expand/Collapse All Grid Groups button in the Grid Header. I know this is possible to do so programmatically outside of the grid but my users want it inside the Grid. 

Thanks,

Humayoon

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