Completed
Last Updated: 12 Aug 2026 13:54 by ADMIN
Release 2026 Q2
If you focus an item, you can resize it with "Ctrl+Arrow keys". If you for example press "Ctrl+Arrow up", the items vertical size shrinks. If you do that repeatedly, it becomes less than 0. If you want to increase the size again, you first have to undo all that negativity, before the items grows again. Ideally, the code should only reduce "ColSpan" and "RowSpan" if its current value is greater than 1.
Completed
Last Updated: 12 Aug 2026 13:52 by ADMIN
Release 2026 Q2

Currently, a TextField value of empty string will produce a blank item in the dropdown.

On the other hand, a null TextField value will produce the fully qualified class name.

Here are possible workarounds: https://blazorrepl.telerik.com/myOlFpFb1465jW8E07

Completed
Last Updated: 12 Aug 2026 13:51 by ADMIN
Release 2026 Q2
The EventCallbacks "OnResize" and "OnReorder" only get invoked when a user is performing the appropriate actions with the mouse, not when using keyboard navigation.
Completed
Last Updated: 12 Aug 2026 13:40 by ADMIN
Release 2026 Q2
Created by: Michal
Comments: 3
Category: Filter
Type: Bug Report
0

Hello,

 at version 12.3.0 TelerikFilter is crashing "at load". Prior this version, same markup = ok.

Error: System.InvalidOperationException: Object of type 'Telerik.Blazor.Components.TelerikFilter' does not have a property matching the name 'ValueChanged'.

also in demo:

https://www.telerik.com/blazor-ui/documentation/components/filter/integration

usage:

<TelerikFilter @bind-Value="@AdvancedFilterValue">
	<FilterFields>
		@foreach (var it in GridDef.ColStore.Where(x => x.Verejny == true))
		{
			<FilterField Name="@it.FldName" Type="@it.FldType" Label="@it.VerejnyNazev"></FilterField>
		}
	</FilterFields>
</TelerikFilter>
Completed
Last Updated: 12 Aug 2026 12:30 by ADMIN
Release 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: 12 Aug 2026 12:12 by ADMIN
Release 2026 Q2
Created by: Stefan
Comments: 5
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

Completed
Last Updated: 12 Aug 2026 12:10 by ADMIN
Release 2026 Q2

With `PersistTabContent="true"`, when tabs start with `Visible="false"` and later become `Visible="true"`, all visible tab contents are instantiated simultaneously instead of only the active tab.

Reproduction: 

@page "/TestPage"

<button @onclick="Load">Load</button>

<TelerikTabStrip PersistTabContent="true">
    <TabStripTab Title="Tab 1" Visible="@_tabsVisible">
        <TestInitComponent Message="Hello from tab1" />
    </TabStripTab>
    <TabStripTab Title="Tab 2" Visible="@_tabsVisible">
        <TestInitComponent Message="Hello from tab2" />
    </TabStripTab>
    <TabStripTab Title="Tab 3" Visible="@_tabsVisible">
        <TestInitComponent Message="Hello from tab3" />
    </TabStripTab>
</TelerikTabStrip>

@code {
    private bool _tabsVisible = false;

    private void Load()
    {
        _tabsVisible = true;
    }
}

TestInitComponent.razor

<h3>TestInitComponent</h3>

@code {

    [Parameter]
    public string Message { get; set; } = string.Empty;

    protected override void OnInitialized()
    {
        base.OnInitialized();
        Console.WriteLine($"TestInitComponent OnInitialized {Message}");
    }
}

Steps: Open page → click Load.

Completed
Last Updated: 12 Aug 2026 12:04 by ADMIN
Release 2026 Q2

The appointments at the start of the day seem accurate. If you scroll down, the position of the appointments does not line up with the grid line for the hour that it starts at or ends at. The issue can be observed in the live demo.

 

Completed
Last Updated: 12 Aug 2026 12:03 by ADMIN
Release 2026 Q3 (Aug)

If the Start and End match exactly, the rendering of the Scheduler breaks in Day view. If another view is used, the event looks as if it is rendered on the previous day.

===

ADMIN EDIT

===

A possible workaround for the time being is to use a custom edit form and implement some kind of validation that prevents the user from selecting the same value for the Start and End of an event.

Completed
Last Updated: 12 Aug 2026 10:12 by ADMIN
Release 2026 Q3 (Aug)
Created by: David
Comments: 0
Category: DropDownList
Type: Bug Report
9

In TelerikSelectBase that the DropDownList inherits, the FieldIdentifier is set only in the OnInitializedAsync method and therefore the FieldIdentitier is never updated. This can cause issues with validation as seen in this example:  https://blazorrepl.telerik.com/GyamPdlf37LXpPAW36.

To reproduce:

  • Select the last item in the tree 7.Garden and change the value in the drop down list to Unsupported - the drop down list shows a red border.
  • Select item 6.Garden from the tree. (Any item in the tree other than 1 will do) - I expect the drop down to not have the red border, yet is does.

For reference, in the TelerikInputBase, the FieldIdentifier is set in the SetParameterAsync and thus it is accordingly updated. See the TextBox behavior in the above sample.

Completed
Last Updated: 12 Aug 2026 10:12 by ADMIN
Release 2026 Q3 (Aug)
Created by: Tim
Comments: 0
Category: Grid
Type: Bug Report
1

If the GridScrollMode.Virtual is enabled for the Grid, and the NoDataTemplate exceeds the height of the Grid container, a user can infinitely scroll inside the table even when there is no data and the template is displaying.

 

===ADMIN EDIT===

A possible workaround is to apply "overflow-y: hidden;" when the NoDataTemplate is shown: REPL link.

Completed
Last Updated: 12 Aug 2026 10:11 by ADMIN
Release 2026 Q3 (Aug)
Hello Telerik Support Team,

We are experiencing a scrolling issue in **Telerik PivotGrid for Blazor (v12)** when both vertical and horizontal scrollbars are present.

**Issue Summary**
When the PivotGrid contains enough expanded data to require both vertical and horizontal scrolling, interacting with one scrollbar causes the grid to unexpectedly reset the other scroll position (jumping back to the top or left-most column).

**Steps to Reproduce**
e.g.: https://demos.telerik.com/blazor-ui/pivotgrid/overview

1. Bind the PivotGrid with a large dataset.
2. Expand a column hierarchy (e.g., Year → Months) to generate horizontal scrolling.
3. Expand multiple row groups (some near the top and some further down) to generate vertical scrolling.
4. Scroll fully to the **right**.
5. Attempt to scroll **down** using the vertical scrollbar or mouse wheel.

   * The grid scrolls down, but the horizontal position resets to the first column.
6. Scroll to the **bottom**.
7. Attempt to scroll **right** using the horizontal scrollbar.

   * The grid scrolls right, but the vertical position resets to the top.

**Actual Behavior**
Scrolling in one direction causes the PivotGrid to reset the scroll position in the other direction.

**Expected Behavior**
Vertical and horizontal scroll positions should remain independent. Scrolling in one direction should not reset the other.

This occurs consistently when multiple row and column groups are expanded and both scrollbars are active.

Please let us know if additional configuration details or a sample project would help.

Regards,
Niraj Phalke
Completed
Last Updated: 11 Aug 2026 15:43 by ADMIN
Release 2026 Q3 (Aug)
Created by: Neil N
Comments: 3
Category: DatePicker
Type: Feature Request
18

I would like the following behavior in the date picker. Perhaps it can be achieved with a parameter similar to the one in UI for ASP.NET AJAX - the FocusedDate property (something like RadDatePicker1.FocusedDate = DateTime.Today.AddDays(30);).

The current behaviour is:

* if date is set, show month of set date
*else show month of current date (today)

Desired behaviour:

* if date is set, show month of set date
* else if min date's month is greater than current date month then show month of min date
* else show month of current date

Here is a code snippet to illustrate the issue:

 

Open the picker - it will start in the month with today's date, but I want it to start at the min date - one month later

<TelerikDatePicker @bind-Value="@theDate" Min="@minDate" Max="@maxDate"></TelerikDatePicker>
@code {
    DateTime theDate = DateTime.Now;
    DateTime minDate = DateTime.Now.AddDays(60);
    DateTime maxDate = DateTime.Now.AddDays(230);
}

 

===

ADMIN EDIT

===

The request also applies to the rest of the pickers - DateTimePicker and DateRangePicker.
Completed
Last Updated: 11 Aug 2026 08:49 by ADMIN
Release 2026 Q3 (Aug)
Created by: Korstiaan
Comments: 0
Category: Grid
Type: Bug Report
0

Bug report

Once the user locks a column through the column menu, they cannot unlock it, because the Unlock option remains disabled, while the Locked option remains enabled.

Regression in version 14.1.0. Potentially related to https://github.com/telerik/blazor/pull/14727

Reproduction of the problem

@page "/"

<TelerikGrid Data="@GridData"
             Pageable="true"
             FilterMode="@GridFilterMode.FilterRow"
             Sortable="true"
             ShowColumnMenu="true"
             Width="700px">
    <GridColumns>
        <GridColumn Field="@(nameof(SampleData.Id))" Width="80px" ShowColumnMenu="false" />
        <GridColumn Field="@(nameof(SampleData.FirstName))" Title="First Name" Id="firstname-column-id" Width="300px" />
        <GridColumn Field="@(nameof(SampleData.LastName))" Title="Last Name" Id="lastname-column-id" Width="300px" />
        <GridColumn Field="@(nameof(SampleData.CompanyName))" Title="Company" Id="companyname-column-id" Width="300px" />
        <GridColumn Field="@(nameof(SampleData.Team))" Title="Team" Id="team-column-id" Width="300px" />
        <GridColumn Field="@(nameof(SampleData.HireDate))" Title="Hire Date" Width="300px" />
    </GridColumns>
</TelerikGrid>

@code {
    private IEnumerable<SampleData> GridData = Enumerable.Range(1, 30).Select(x => new SampleData
        {
            Id = x,
            FirstName = $"FirstName {x}",
            LastName = $"LastName {x}",
            CompanyName = $"Company {x}",
            Team = "team " + x % 5,
            HireDate = DateTime.Now.AddDays(-x).Date
        });

    public class SampleData
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string CompanyName { get; set; }
        public string Team { get; set; }
        public DateTime HireDate { get; set; }
    }
}

Current behavior

Cannot unlock a locked column, the Unlock option remains disabled.

Expected/desired behavior

The Unlock and Lock options in the column menu must reflect the current column state.

Completed
Last Updated: 07 Aug 2026 13:31 by ADMIN
Release 2026 Q3 (Aug)
Created by: Nathan
Comments: 3
Category: UI for Blazor
Type: Feature Request
23
I'd like to be able to change the built-in icons that the components use. I currently can do that with custom solutions but I need an option to easily change all icons on a global app level (e.g. all save icons, all arrow-down icons, etc.). I have a custom icon set and I want to ensure consistency in the icons used throughout the app.
Completed
Last Updated: 06 Aug 2026 09:26 by ADMIN
Release 2026 Q3 (Aug)

The TreeView OnItemContextMenu event should fire only for the clicked item, but it fires for its parents too. The issue started occurring in version 13.0.0.

Test page

https://www.telerik.com/blazor-ui/documentation/components/treeview/events#example

Completed
Last Updated: 04 Aug 2026 07:58 by ADMIN
Release 2026 14.1.0 (Jul)

Reproduction with Data parameter

https://blazorrepl.telerik.com/GJYPlrEW485dZtjX55

Reproduction with OnRead

I made a Blazor REPL reproduction: https://blazorrepl.telerik.com/mcuCGpYr4223mhWY49. Run and observe the person label is overlapping the dropdown.

How to reproduce:

  1. Get code from the Remote Data Example.
  2. Surround the ComboBox with a TelerikFloatingLabel, it will then look like this:
    <TelerikFloatingLabel Text="Person">
    <TelerikComboBox 
                    TItem="@Person" TValue="@int"
                     ScrollMode="@DropDownScrollMode.Virtual"
                     OnRead="@GetRemoteData"
                     ValueMapper="@GetModelFromValue"
                     ItemHeight="30"
                     PageSize="20"
                     TextField="@nameof(Person.Name)"
                     ValueField="@nameof(Person.Id)"
                     @bind-Value="@SelectedValue"
                     Filterable="true" FilterOperator="@StringFilterOperator.Contains">
        <ComboBoxSettings>
            <ComboBoxPopupSettings Height="200px" />
        </ComboBoxSettings>    
    </TelerikComboBox>
    </TelerikFloatingLabel>
Completed
Last Updated: 03 Aug 2026 06:44 by ADMIN
Release 2026 Q3 (Aug)
Created by: Johan
Comments: 1
Category: MultiSelect
Type: Feature Request
27

Hi,

I would like checkbox support including the check all checkbox on the multiselect component like: https://docs.telerik.com/devtools/aspnet-ajax/controls/combobox/functionality/checkbox-support

The url below shows how to create custom checkboxes in the multiselect component but adding a check all checkbox in the headertemplate does not update the multiselect popup

https://docs.telerik.com/blazor-ui/knowledge-base/multiselect-checkbox-in-dropdown?_ga=2.50111909.206897922.1631541466-694624900.1630583797&_gac=1.246637872.1631604077.EAIaIQobChMI8PnX6Pb98gIVkwCLCh381AjMEAAYASAAEgLROPD_BwE

Completed
Last Updated: 31 Jul 2026 14:27 by ADMIN
Release 2026 Q3 (Aug)
Created by: Mark
Comments: 0
Category: FileSelect
Type: Feature Request
14

UI for Blazor version 5.0 improved the FileSelect Stream performance by removing legacy code that meant to support older .NET versions.

However, the Stream performance is still worse and the component works slower, compared to the standard Blazor InputFile.

Completed
Last Updated: 31 Jul 2026 13:25 by ADMIN
Release 2026 Q3 (Aug)
Created by: Charles
Comments: 0
Category: TextBox
Type: Bug Report
0

Description

An input with type="password" should not have a default role. See:
w3c/html-aria#422
https://w3c.github.io/html-aria/#dfn-no-corresponding-role

Steps To Reproduce

Inspect the rendering of the password input in this demo: https://demos.telerik.com/blazor-ui/textbox/password

Actual Behavior

The element renders a role="textbox" attribute.

Expected Behavior

The element does not render a role="textbox" attribute.

Browser

All

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

No response

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