Completed
Last Updated: 05 Dec 2025 11:58 by ADMIN
Release 2026 Q1 (Feb)

Description

Regression introduced in v9.0.0.

Initial binding to a property works, but when either the RemoveAttributes or the StripTags parameter is set, on changing the Editor value, two-way binding does not work and the new Editor value is not reflected in the property value.

Potentially related to #3887

Steps To Reproduce

  1. Run the following example:
<p role="status">Current Editor value: @CurrentEditorText</p>

<TelerikEditor @bind-Value="@CurrentEditorText">
    <EditorSettings>
        <EditorPasteSettings ConvertMsLists="@true"
                             RemoveAllAttributes="@true"
                             RemoveAttributes="@(new List<string> { "lang" })"
                             RemoveHtmlComments="@true"
                             RemoveMsClasses="@true"
                             RemoveMsStyles="@true"
                             StripTags="@( new List<string> { "h1" })">
        </EditorPasteSettings>
    </EditorSettings>
</TelerikEditor>


@code {
    private string CurrentEditorText { get; set; } = @"<strong>initial</strong><span>value</span>";

    public List<string> RemoveAttributes { get; set; } = new List<string>() { "data-id" };

    public List<string> StripTags { get; set; } = new List<string>() { "font" };
}
  1. Type in the Editor's content area

Actual Behavior

The CurrentEditorText property value is not updated.

Expected Behavior

The CurrentEditorText property value is updated.

Browser

All

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

8.1.1

Completed
Last Updated: 05 Dec 2025 08:35 by ADMIN

---

ADMIN EDIT

A workaround is to initialize the RemoveAttributes list:

<TelerikEditor @bind-Value="@EditorContent">
    <EditorSettings>
        <EditorPasteSettings 
                             RemoveAttributes="@( new List<string>() )"
                            >
        </EditorPasteSettings>
    </EditorSettings>
</TelerikEditor>

@EditorContent

@code{
    string EditorContent { get; set; }
}

---

Completed
Last Updated: 24 Nov 2025 15:42 by ADMIN
Release 12.0.0
The WindowAction's OnClick event handler is not firing if the project target framework is .NET10.
Completed
Last Updated: 17 Nov 2025 09:14 by ADMIN
Release 2026 Q1 (Feb)
Created by: Craig
Comments: 1
Category: Chat
Type: Bug Report
1

Hi,

When submitting a chat message using the Chat component, it is possible to lose recently entered text.

I believe this is because:

  1. The TextArea in the Chat component has a debounce delay (the default 150ms delay)
  2. Pressing enter (or clicking the send button) fires the SendMessageAsync method instantly
  3. SendMessageAsync uses the last text received from the TextArea, but this can be up to 150ms behind due to the debounce delay

This is reproducible on the Chat component documentation page, https://www.telerik.com/blazor-ui/documentation/components/chat/overview#creating-blazor-chat:

  1. Type in some text
  2. Wait 150ms (i.e., wait for the button to enable, otherwise the enter keypress and button clicks are ignored)
  3. Type some more text and quickly hit enter (or press the button)

Depending on the timing, the last few characters/words will be lost and not included in the message.

I encounter this issue in version 11 with server side rendering, but the documentation page appears to be using version 12 with web assembly.

Thanks,

Craig

 

Completed
Last Updated: 17 Nov 2025 07:24 by ADMIN
Created by: Jamie
Comments: 4
Category: UI for Blazor
Type: Bug Report
0

After upgrading to 12.0.0, the Content does not change when clicking tabs. I always see the Content of the first tab.

My project targets .net8.

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Bernd
Comments: 0
Category: Charts
Type: Feature Request
3

Currently the bubble sizes in the Chart are determined automatically, according to an internal algorithm.

Please add parameters for setting specific min and max bubble sizes by the application.

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Jason
Comments: 0
Category: DropDownButton
Type: Bug Report
1

When using the OnClick event on a DropDownButtonItem, the MouseEventArgs parameter is always null. However, if the OnClick event is used on the main TelerikDropDownButton component, the MouseEventArgs works correctly.

REPL reproduction - https://blazorrepl.telerik.com/mfYdbbPQ37jhZlMq47

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0

We are experiencing an issue where the ExportToPdfAsync() method on TelerikGrid is returning Excel data (XLSX format) instead of PDF data. This is causing MIME type errors when trying to process the exported data as a PDF.

 

===ADMIN EDIT===

Workaround

In the meantime, a possible workaround would be to use the document processing library (make sure the correct packages are installed for it) and import the xlsx file to a workbook, and then export the workbook to PDF. Here is an improvised example that demonstrates this by saving the file in your wwwroot folder as a pdf.

@inject IWebHostEnvironment HostingEnvironment

<TelerikGrid Data="@bookList" Height="75svh" Resizable="true" Sortable="true" Pageable="true" PageSize="15"
             FilterMode="@GridFilterMode.FilterMenu" SelectionMode="@GridSelectionMode.Multiple"
             SelectedItems="@SelectedBooks" @ref="@BookGrid"
             SelectedItemsChanged="@((IEnumerable<BookInfo> sel) => OnRowSelect(sel))">
    <GridToolBarTemplate>
        <TelerikButton OnClick="@GenerateReport">Generate PDF</TelerikButton>
    </GridToolBarTemplate>
    <GridExport>
        <GridPdfExport AllPages="true" PageOrientation="GridPdfExportPageOrientation.Landscape"
                       PaperSize="GridPdfExportPaperSize.A3" />
    </GridExport>
    <GridColumns>
        <GridCheckboxColumn CheckBoxOnlySelection="true"></GridCheckboxColumn>
        <GridColumn Field="ISBN">
            <HeaderTemplate><b>ISBN</b></HeaderTemplate>
        </GridColumn>
        <GridColumn Field="Author">
            <HeaderTemplate><b>Author</b></HeaderTemplate>
        </GridColumn>
        <GridColumn Field="Title">
            <HeaderTemplate><b>Title</b></HeaderTemplate>
        </GridColumn>
        <GridColumn Field="Genre">
            <HeaderTemplate><b>Genre</b></HeaderTemplate>
        </GridColumn>
        <GridColumn Field="PublishedYear">
            <HeaderTemplate><b>Year</b></HeaderTemplate>
        </GridColumn>
        <GridColumn Field="CopiesAvailable">
            <HeaderTemplate><b>Copies</b></HeaderTemplate>
        </GridColumn>
    </GridColumns>
</TelerikGrid>

@code {
    private async Task GenerateReport()
    {
        isLoading = true;
        var pdfStream = await BookGrid.ExportToPdfAsync();

        // The stream is actually XLSX, so convert it to PDF
        using var ms = new MemoryStream(pdfStream.ToArray());

        var xlsxProvider = new Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider();
        var workbook = xlsxProvider.Import(ms);

        var rootPath = HostingEnvironment.WebRootPath;
        var saveLocation = Path.Combine(rootPath, "LibraryBooks.pdf");
        var pdfProvider = new Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider();
        using (var fileStream = new FileStream(saveLocation, FileMode.Create))
        {
            pdfProvider.Export(workbook, fileStream);
        }
    }

    public class BookInfo
    {
        public string ISBN { get; set; }
        public string Author { get; set; }
        public string Title { get; set; }
        public string Genre { get; set; }
        public int PublishedYear { get; set; }
        public int CopiesAvailable { get; set; }
    }

    private List<BookInfo> bookList = new()
    {
        new BookInfo { ISBN = "978-0451524935", Author = "George Orwell", Title = "1984", Genre = "Dystopian", PublishedYear = 1949, CopiesAvailable = 4 },
        new BookInfo { ISBN = "978-0439139601", Author = "J.K. Rowling", Title = "Harry Potter and the Goblet of Fire", Genre = "Fantasy", PublishedYear = 2000, CopiesAvailable = 7 },
        new BookInfo { ISBN = "978-0140449266", Author = "Homer", Title = "The Odyssey", Genre = "Epic Poetry", PublishedYear = -800, CopiesAvailable = 2 }
    };

    private TelerikGrid<BookInfo> BookGrid;
    private List<BookInfo> SelectedBooks = new();
    private bool isLoading = false;

    private void OnRowSelect(IEnumerable<BookInfo> selected)
    {
        SelectedBooks = selected.ToList();
    }
}

 

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Plastic
Comments: 6
Category: Grid
Type: Bug Report
1
A Grid component with a ColumnMenu increases memory usage due to event handler leaks specifically associated with the ColumnMenu.
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Rami
Comments: 1
Category: MultiSelect
Type: Bug Report
1

I was hoping to use the new AllowCustom feature to let users name a few areas, save those names in the backend and later show them as preselected when the user comes back so they don't have to retype the names every time they do an operation. But alas, the AllowCustom seems to only allow preselecting from what's in the Data list of values.

So code like below doesn't actually show a chip for Rome even though it's preselected. There is a workaround of setting the Data property to a list that contains the custom values I need preselected, but it feels clumsy and with the custom values I feel Multiselect should also check the selected values list for chips to render.

<TelerikMultiSelect 
   @bind-Value="@SelectedCities"
   TItem="string" TValue="string"
   AllowCustom="true"                   
   Width="400px">
</TelerikMultiSelect>

<span>Selected: @SelectedCities.Count</span>

@code {
    private List<string> SelectedCities { get; set; } = new() {"Rome"};
}

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Dan
Comments: 7
Category: Dialog
Type: Feature Request
19
Pressing the Enter key should trigger the Ok button in the Prompt Dialog
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Bohdan
Comments: 2
Category: DockManager
Type: Bug Report
3
Hi Telerik Team,

While working with the DockManager component we encountered a few issues and want to request a minor change:

Inconsistent pane header height
   - When panes are in different states (headers displayed as a Tab vs. as a PaneHeader), their heights differ.  
   - Feature request: please consider introducing size enums (e.g. Small / Medium / Large) so that developers can adjust the header size. At the very least, making the heights consistent by default would help.

Thanks.
Bohdan
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Plastic
Comments: 0
Category: Grid
Type: Bug Report
1

A Grid component with GridToolBar increases memory usage due to event handler leaks, specifically associated with the GridToolBar and ColumnMenuToolBar.

 

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Gal
Comments: 0
Category: PDFViewer
Type: Bug Report
4
The quality of the PDFViewer document in the print preview popup has declined since version 6.2.0.
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
After moving down to the desired DropDownButtonItem with the arrow key, the "enter" key will not trigger the OnClick event of the selected DropDownButtonItem.
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0

I have a scheduler, and am using a custom Edit handler. I need to support recurrence, and editing recurring events. When the use double-clicks on a recurring event, there is a dialog that asks whether they would like to edit the occurrence or the entire series.

I want to be able to capture the results of this dialog. `SchedulerEditEventArgs` doesn't include any attributes that track this.

 

===========

ADMIN EDIT

===========

The implementation of this enhancement could be covered by either including the corresponding attributes in the SchedulerEditEventArgs or by exposing a Template for the RecurrenceDialog.

Note: You may also check the Ability to directly edit an occurence or the series, without the prompt asking you to choose feature request as the implementation of both features will most likely be covered in one release.

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Naved
Comments: 5
Category: FileManager
Type: Feature Request
26
Currently, the upload functionality of the FileManager allows uploading only one file. I'd like to be able to upload multiple files.
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: David Cresswell
Comments: 0
Category: PDFViewer
Type: Bug Report
2
The PdfViewer GetFileAsync method returns null even if a PDF document is loaded in the component.
Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0
Created by: Philip
Comments: 0
Category: TimePicker
Type: Bug Report
14

Description

Regression introduced in version 10.0.0. The TimePicker's value must be null initially and the system time should be at least 55 minutes past the hour (e.g., 13:55 or 14:57).

Steps To Reproduce

  1. Set the time on your machine to 55 past the hour, e.g., 13:55.
  2. Open a new instance of Chrome and navigate to https://blazorrepl.telerik.com/mpFEYBOi12ooskUK19
  3. Run the example
  4. Click in the clock icon in the picker, to open its dropdown.
  5. Click the Set button.

Actual Behavior

The following error is thrown:

Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
Unhandled exception rendering component: Hour, Minute, and Second parameters describe an un-representable DateTime.
System.ArgumentOutOfRangeException: Hour, Minute, and Second parameters describe an un-representable DateTime.

Expected Behavior

No error is thrown and the time that is automatically highlighted in the dropdown is set, after clicking the "Set" button.

Browser

All

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

9.1.0

Completed
Last Updated: 12 Nov 2025 10:58 by ADMIN
Release 12.0.0

Hello,

I’ve run into a reproducible issue with the Blazor Grid in Adaptive mode. After the grid adapts to a smaller container and then the container is expanded again, the data rows scroll while the header remains fixed, so the header and data become detached.

I’m attaching three screenshots that show the sequence:

  1. 01.png — Grid in normal (non-adaptive) state.
  2. 02.png — After shrinking the container until the grid switches to Adaptive.
  3. 03.png — After expanding the container again; scrolling the grid shows the header no longer tracks with the data.

Steps to reproduce

  1. Open the REPL I’m providing: [REPL link here].
  2. Shrink the container (e.g., resize the pane/window) until the grid switches to Adaptive mode.
  3. Expand the container back to a larger width so the grid returns to its standard table view.
  4. Scroll the grid using the scrollbar/slider: the body content scrolls, but the header stays static and is no longer aligned with the data.

Expected behavior

Header and data remain synchronized—when the grid is scrolled horizontally/vertically, both header and rows should scroll together.

Actual behavior

After returning from Adaptive to the standard layout, the header does not move with the rows when scrolling; it appears “detached”.

Notes

  • I did not add any custom CSS related to header/body layout in the demo.
  • I haven’t identified a reliable workaround yet.


Please let me know if this is a known issue, if there’s a fix/workaround, or if you need any additional details.

REPL: https://blazorrepl.telerik.com/cfkXlLFd30pGcc6i09?_gl=1*4qgvh1*_gcl_au*OTEyODU4MzMuMTc1NzU3NDk1Ng..*_ga*MTc1OTQ2OTkzNy4xNzU3NTc0ODY4*_ga_9JSNBCSF54*czE3NTk5OTkxMjgkbzEwJGcxJHQxNzYwMDAxNTkwJGo1MyRsMCRoMA..

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