Declined
Last Updated: 09 Apr 2026 14:58 by ADMIN
Created by: Andreas
Comments: 7
Category: Editor
Type: Bug Report
1

When a table row does not have any cells, there might be lots of script errors when hovering the empty row with the mouse.

The error is the following:
Uncaught RangeError: Not a table node: doc

    get http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    get http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    decorations http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    decorations http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Fa http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    someProp http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Fa http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    updateStateInner http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    updateState http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    dispatch http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Bu http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    mousemove http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    mousemove http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Vo http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    someProp http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Vo http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    i http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Jo http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    someProp http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Jo http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Wa http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    Wa http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    initEditor http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    initialize http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    d http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    initComponent http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    initEditor http://localhost:5045/_content/Telerik.UI.for.Blazor/js/telerik-blazor.kh4xf5u23f.js:1
    processJSCall http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    beginInvokeJSFromDotNet http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _invokeClientMethod http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _processIncomingData http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    onreceive http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    onmessage http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    connect http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    connect http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _startTransport http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _createTransport http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _startInternal http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    start http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _startInternal http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    _startWithStateTransitions http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    start http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    startConnection http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    startCore http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    start http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    rr http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    or http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    startCircutIfNotStarted http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    resolveRendererIdForDescriptor http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    determinePendingOperation http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    refreshRootComponents http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    rootComponentsMayRequireRefresh http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    rootComponentsMayRequireRefresh http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    onDocumentUpdated http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    Ki http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    Vi http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    <anonymous> http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1
    <anonymous> http://localhost:5045/_framework/blazor.web.ax6tuj8tun.js:1

 

Sometimes we even have a server error:
Microsoft.JSInterop.JSException: Not a table node: table_wrapper
RangeError: Not a table node: table_wrapper
    at https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1557112
    at pl.get (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1558816)
    at https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1638148
    at Be.decorations (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1638538)
    at https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1529498
    at Wa.someProp (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1548718)
    at Fa (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1529464)
    at Wa.updateStateInner (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1545305)
    at Wa.update (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1544591)
    at Wa.setProps (https://somesite/caesar/_content/Telerik.UI.for.Blazor/js/telerik-blazor.js?x=25.1.7.1096:23:1544734)
   at Microsoft.JSInterop.JSRuntime.InvokeAsync[TValue](Int64 targetInstanceId, String identifier, Object[] args)
   at Telerik.Blazor.Components.TelerikEditor.SetOptions()
   at Telerik.Blazor.Components.TelerikEditor.OnParametersSetAsync()
   at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)

The server error is really hard to recreate, but it seems like users that has a slow computer and hovers the editor directly when loading gets this error sometimes...

Here is the source code (hovering the empty row will generate scripting errors):

<TelerikEditor Height="300px" @bind-Value="@Value" EditMode="Telerik.Blazor.EditorEditMode.Iframe" ReadOnly="true">
</TelerikEditor>

@code {
    public string Value { get; set; } =
            @"
<table>
    <tbody>
        <tr>
            <td>
               Some text
            </td>
        </tr>
        <tr style=""height: 24px"">
        </tr>
        <tr>
            <td>
                Some text
            </td>
        </tr>
    </tbody>
</table>
    ";
}

Completed
Last Updated: 09 Apr 2026 14:18 by ADMIN
Release 2025 Q3 (Aug)
Created by: Stefan
Comments: 3
Category: Upload
Type: Bug Report
8

Description

File data is not available in the Upload's OnSuccess event.

Regression in version 9.0.0 introduced with the addition of the chunk upload functionality.

https://github.com/telerik/blazor/blob/master/js/telerik-blazor/src/upload/upload.ts#L282-L288

Steps To Reproduce

  1. Attach a handler to the OnSuccess event:
<TelerikUpload SaveUrl="/api/upload/save"
               RemoveUrl="/api/upload/remove"
               OnSuccess="@OnSuccessHandler" />

@code {
    async Task OnSuccessHandler(UploadSuccessEventArgs e)
    {
        foreach (var file in e.Files)
        {
            Console.WriteLine($"Name = {file.Name}, Size = {file.Size}, Extension = {file.Extension}");
        }

        StateHasChanged();
    }
}
  1. Upload a file and try to access its Name, Size, and Extension properties in the event handler.

Actual Behavior

The properties have their default values (null for Name and Extension and 0 for Size).

Expected Behavior

The actual file data is accessible in the OnSuccess event handler.

Browser

All

Last working version of Telerik UI for Blazor (if regression)

8.1.1

Unplanned
Last Updated: 09 Apr 2026 13:32 by Stéphane

Bug report

Reproduction of the problem

1. Set a culture in the app, e.g.,

Program.cs

CultureInfo.DefaultThreadCurrentCulture = new CultureInfo("fr-CA");
CultureInfo.DefaultThreadCurrentUICulture = new CultureInfo("fr-CA");

2. Add a basic Scheduler with Agenda view enabled.

Current behavior

The weekdays in the Agenda view date headers are not translated in the language set by the culture.

Expected/desired behavior

The weekdays in the Agenda view are translated. Note that they are properly translated in other views, e.g., Week and Month.

Environment

  • Kendo/Telerik version: 13.1.0
  • Browser: [all ]
Completed
Last Updated: 09 Apr 2026 12:45 by ADMIN
Release 2026 Q2

OnChange and OnBlur event for editors (TelerikTextBox, NumericTextBox, and others) is not fired in InCell edit mode with Tab key.

 

Planned
Last Updated: 09 Apr 2026 12:43 by ADMIN
Scheduled for 2026 Q2

Telerik input components inside EditorTemplate render the whole grid on each keystroke

 

<AdminEdit>

As a workaround, you can use the standard Input components provided by the framework together with a CSS class that would visually make them like the Telerik Input Components. An example for the TextArea:

<InputTextArea class="k-textarea" @bind-Value="@myValue"></InputTextArea>

</AdminEdit>

Planned
Last Updated: 09 Apr 2026 12:43 by ADMIN
Scheduled for 2026 Q2
Created by: Adam
Comments: 1
Category: Grid
Type: Bug Report
1

The Grid performance worsens progressively with each subsequent edit operation. Please optimize that.

Test page: https://blazorrepl.telerik.com/mJuHFNbb17FpJu9b54

Click on a Price or Quantity cell to start edit mode and tab repetitively to observe the degradation.

Unplanned
Last Updated: 09 Apr 2026 12:41 by ADMIN
Scheduled for 2026 Q2

When ActiveTabId is null, the TabStrip selects the first tab automatically, but does not render its content.

<TelerikTabStrip @bind-ActiveTabId="@TabStripActiveTabId">
    <TabStripTab Title="First" Id="t1">
        First tab content.
    </TabStripTab>
    <TabStripTab Title="Second" Id="t2">
        Second tab content.
    </TabStripTab>
    <TabStripTab Title="Third" Id="t3">
        Third tab content.
    </TabStripTab>
</TelerikTabStrip>

@code {
    private string? TabStripActiveTabId { get; set; }
}

Completed
Last Updated: 09 Apr 2026 11:56 by ADMIN
Release 2026 Q2
Created by: Wolf-Günter
Comments: 2
Category: FileManager
Type: Bug Report
5
If the FileManager is nested inside an EditForm or a TelerikForm, it will trigger exceptions. Some of the nested components in the FileManager will require a ValueExpression, as if they are related to the form's EditContext.
Planned
Last Updated: 09 Apr 2026 10:48 by ADMIN
Scheduled for 2026 Q2
When the floating pane is initially set to Visible=false, docking no longer works after it is shown.
Completed
Last Updated: 09 Apr 2026 08:35 by ADMIN
Release 2026 Q2
I am using a bool property to control whether the columns of the Grid would be virtualized. When I try to toggle the value of this property the feature is not enabled or disabled accordingly. 
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>

Planned
Last Updated: 01 Apr 2026 06:19 by ADMIN
Scheduled for 2026 Q2

When SchedulerGroupOrientation is set to vertical, increasing the height of the `SchedulerResourceGroupHeader` breaks the rendering of the Scheduler cells, which causes misalignment of the appointments. In my scenario, I want to have a Button and an Icon in the group header cell.

Reproduction example: https://blazorrepl.telerik.com/wJElGYvF02XSsN6j42

Declined
Last Updated: 31 Mar 2026 09:43 by ADMIN

Issue: Opening and closing a window will cause the window to reopen with each following OnClick. This seems to have been introduced with the upgrade to .net10

Code: Below is an example used on the basic Telerik Blazor template. Copy this and replace Home.razor with it.

@page "/"

<PageTitle>Telerik Blazor App | Home</PageTitle>

<div id="home-page">
    <HomeSvg />

    <h1>Hello, Telerik UI for Blazor!</h1>

    <p>Welcome to your new Telerik Blazor app.</p>

    <TelerikButton OnClick="OpenWindow1">Click Here First</TelerikButton>
    <TelerikButton OnClick="OpenWindow2">Click Here Second</TelerikButton>
    <TelerikButton OnClick="@(async () => {await Task.Delay(100);})">Unrelated OnClick</TelerikButton>


</div>

<TelerikWindow Visible="ShowWindow1">
    <WindowActions>
        <WindowAction OnClick="CloseWindow1" Name="Close"></WindowAction>
    </WindowActions>
    <WindowContent>
        <span>Moving window now will help find this window in next step, but not necessary to replicate bug.</span>
        <br />
        <span>Close window using 'X'.</span>
    </WindowContent>
</TelerikWindow>

<TelerikWindow Visible="ShowWindow2">
    <WindowActions>
        <WindowAction OnClick="CloseWindow2" Name="Close"></WindowAction>
    </WindowActions>
    <WindowContent>
        <span>Window 1 shouldn't be appearing now, but it it is. Window 1 may be behind this window if you didn't drag in previous step.</span>
        <br />
        <span>If you close these windows, and click the 'Unrelated OnClick' button, both of these windows will reappear, despite just firing Task.Delay(100)</span>
    </WindowContent>
</TelerikWindow>

<style>
    #home-page {
        margin-left: auto;
        margin-right: auto;
        max-width: max-content;
        text-align: center;
        font-size: var(--kendo-font-size-xl);
    }

    @@media (min-height: calc(56px + 50px + 400px)) {
        /* header + footer + home page container*/
        #home-page {
            margin-top: calc(50vh - 28px - 25px - 200px);
        }
    }
</style>

@code {
    public bool ShowWindow1 { get; set; }
    public bool ShowWindow2 { get; set; }

    public async Task OpenWindow1()
    {
        ShowWindow1 = true;
    }

    public async Task OpenWindow2()
    {
        ShowWindow2 = true;
    }

    public void CloseWindow1()
    {
        ShowWindow2 = false;
        StateHasChanged();
    }

    public void CloseWindow2()
    {
        ShowWindow2 = false;
    }
}


In Development
Last Updated: 27 Mar 2026 14:34 by ADMIN
Scheduled for 2026 Q2
In our serverside blazor application we use the Telerik's DateTimePicker. When we type values in to the date time picker control, it jumps to the next section or to the end before completing the currect section. We use the format 'yyyy-MM-dd HH:mm'

It does not happen always and I think it is happenning when the internet connection is slow and it shows a Javascript error as well (screenshots below)
Completed
Last Updated: 26 Mar 2026 12:49 by ADMIN
Release 2026 Q2

Set the PdfViewer document (data) value to null. As a result, an endless loader will appear.

===

ADMIN EDIT

===

A possible workaround for the time being is to re-initialize the component after clearing the file: https://blazorrepl.telerik.com/cHYwQola24zzBOAd02.

Completed
Last Updated: 26 Mar 2026 07:28 by ADMIN
Release 2026 Q2
Created by: Robert
Comments: 3
Category: Grid
Type: Bug Report
0
A virtual Grid does not handle well dynamic RowHeight changes. The virtual scrollbar is not refreshed and scrolling breaks.
Unplanned
Last Updated: 25 Mar 2026 13:06 by ADMIN
Scheduled for 2026 Q2
Created by: Jeremi
Comments: 2
Category: UI for Blazor
Type: Bug Report
0

Description

When the dropdown is open, the button's aria-controls attribute references a value that matches the popup's data-id, not its actual id. Since aria-controls must point to an element's id, the attribute is invalid and no element in the DOM matches the reference, breaking the accessible relationship between the button and its popup. 

Button renders:

aria-controls="50dc5df2-b83e-41bd-8c34-98470aba77c6"

Popup element has:

data-id="50dc5df2-b83e-41bd-8c34-98470aba77c6"
id="8630d4e4-2f22-4eaf-b96c-7cae113b70ed"

Steps to Reproduce

  1. Add a TelerikDropDownButton using the standard Telerik example (source below).
  2. Open the dropdown and inspect the HTML or run a Lighthouse audit.
<TelerikDropDownButton Icon="@SvgIcon.Share" OnClick="@(()=>OnItemClick("Primary"))">
    <DropDownButtonContent>Share</DropDownButtonContent>
    <DropDownButtonItems>
        <DropDownButtonItem Icon="@SvgIcon.Facebook" OnClick="@(()=>OnItemClick("Facebook"))">Facebook</DropDownButtonItem>
        <DropDownButtonItem Icon="@SvgIcon.Twitter" OnClick="@(()=>OnItemClick("Twitter"))">Twitter</DropDownButtonItem>
        <DropDownButtonItem Icon="@SvgIcon.Linkedin" OnClick="@(()=>OnItemClick("Linkedin"))">Linkedin</DropDownButtonItem>
        <DropDownButtonItem Icon="@SvgIcon.Reddit" OnClick="@(()=>OnItemClick("Reddit"))">Reddit</DropDownButtonItem>
    </DropDownButtonItems>
</TelerikDropDownButton>


Declined
Last Updated: 25 Mar 2026 11:23 by ADMIN
Scheduled for 2026 Q2

DatePicker cursor not advancing after month input. The problem arises when dd/MMM/yyyy format is applied.

To reproduce the issue open this REPL example. Type any date in the second DatePicker. When inserting a month value the cursor is not moved to the year section.

After inserting a month the cursor should be moved to the year section. As when no format is applied (the first DatePicker)
Completed
Last Updated: 24 Mar 2026 14:04 by ADMIN
Release 2026 Q2
Created by: Ola
Comments: 0
Category: MultiColumnComboBox
Type: Bug Report
2
We are using the TelerikMultiColumnComboBox in AdaptiveMode.Auto and with an OnRead filter.

On small viewports and entering something in the searchbox, the key is cleared after entering just one char. This is only happening in the mobile view, otherwise it works fine and one can enter more characters.
Completed
Last Updated: 24 Mar 2026 14:03 by ADMIN
Release 2026 Q2

The Tooltip component throws a JavaScript error when the user opens an adaptive dropdown component and tries to interact with it:

Uncaught TypeError: popup.isParent is not a function

Here is a test page. Open the DropDownList on a narrow screen and click on the adaptive ActionSheet.

 

<TelerikButton Class="tooltip-target" Title="Telerik Tooltip">Button</TelerikButton>

<TelerikDropDownList Data="@ListItems"
                     @bind-Value="@SelectedValue"
                     TextField="@nameof(ListItem.Text)"
                     ValueField="@nameof(ListItem.Id)"
                     AdaptiveMode="@AdaptiveMode.Auto"
                     Width="300px" />
<TelerikTooltip TargetSelector=".tooltip-target"
                ShowOn="@TooltipShowEvent.Hover" />

@code {
    private List<ListItem> ListItems { get; set; } = new();

    private int SelectedValue { get; set; } = 3;

    protected override void OnInitialized()
    {
        ListItems = new List<ListItem>();
        for (int i = 1; i <= 5; i++)
        {
            ListItems.Add(new ListItem()
            {
                Id = i,
                Text = $"Item {i}",
                Category = $"Category {i % 6 + 1}"
            });
        }
        base.OnInitialized();
    }

    public class ListItem
    {
        public int Id { get; set; }
        public string Text { get; set; } = string.Empty;
        public string Category { get; set; } = string.Empty;
    }
}

 

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