In version 15.1.0, the Editor causes a browser freeze when it contains a custom tool and the Value is changed programmatically. It works as expected in version 15.0.1.

The issue occurs only in WebAssembly apps.

Test page:

@using Telerik.Blazor.Components.Editor

<TelerikButton OnClick="@(() => EditorValue = "<p>baz</p><p>baz</p>")" ButtonType="@ButtonType.Button">Change Editor Value</TelerikButton>

<TelerikEditor Tools="@EditorTools"
               @bind-Value="@EditorValue">
    <EditorCustomTools>
        <EditorCustomTool Name="CustomEditorTool">
            custom tool here
        </EditorCustomTool>
    </EditorCustomTools>
</TelerikEditor>

@code {
    private string EditorValue { get; set; } = @"<p>foo</p><p>bar</p>";
    private List<IEditorTool> EditorTools { get; set; } = new();

    protected override void OnInitialized()
    {
        EditorTools.Add(new CustomTool("CustomEditorTool"));

        base.OnInitialized();
    }
}

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
    }
}

Example:

<PageTitle>Home</PageTitle>

<div>
    <TelerikTextBox Width="20rem" Placeholder="Pallet" DebounceDelay="1000" @bind-Value="@_textInput" OnChange="@(async (input) => await OnInputChanged(input))" />
</div>
<p>@_textInput</p>


@code {
    private string? _textInput;

    private async Task OnInputChanged(object input)
    {
        Console.WriteLine($"Immediate: function parameter: {input}, bound variable: {_textInput}");
        await Task.Delay(1000);
        Console.WriteLine($"Delayed: function parameter: {input}, bound variable: {_textInput}");
        //Make the OnChange event receive the immediate value when the DebounceDelay is set
    }
}

The DebounceDelay is set to 1 second to highlight the behavior, although we have observed it with delays less than 100 milliseconds when the input is from a barcode scanner and the Enter is part of the scan. Start the sample, type "123" in the input, and hit enter within 1 second.

The output in the console is:
Immediate: function parameter: , bound variable:
Delayed: function parameter: , bound variable: 123

With Blazor server, clicking the NOW button (obviously) sets the time to the time on the server since that's where the code is running. Is there a way to trap the NOW button click or somehow give it an offset or define the value that NOW means so NOW will mean the time that the user is sitting in?

---

TELERIK EDIT

In the meantime, here are a few possible workarounds:

1. Use the DateTimePicker's ValueChanged event to detect new values that are very close or match the server's current DateTime. In such cases, you can assume that the user has clicked on TODAY / NOW, and set the local user time as a component value.

Server Time on UI Refresh: @DateTime.Now.ToLongTimeString()
<br />
User Local Time on Page Load: @LocalTime?.ToLongTimeString()
<br />
User Local Time Offset: @LocalOffset
<br />
<br />

<TelerikDateTimePicker Value="@PickerValue"
                       ValueChanged="@( (DateTime? newValue) => PickerValueChanged(newValue) )"
                       ValueExpression="@( () => LocalTime )"
                       Format="yyyy-MMM-dd HH:mm:ss"
                       Width="240px" />

<!-- Move JS code to a separate JS file in production -->
<script suppress-error="BL9992">
    function getLocalTime() {
        var d = new Date();
        return d.getTimezoneOffset();
    }
</script>

@code {
    private DateTime? PickerValue { get; set; }
    private DateTime? LocalTime { get; set; }
    private int LocalOffset { get; set; }

    private void PickerValueChanged(DateTime? newValue)
    {
        DateTime serverNow = DateTime.Now;
        DateTime utcNow = DateTime.UtcNow;
        TimeSpan nowTolerance = new TimeSpan(0, 0, 10);

        if (newValue - serverNow < nowTolerance)
        {
            PickerValue = utcNow.AddMinutes(-LocalOffset);
        }
        else
        {
            PickerValue = newValue;
        }
    }

    protected override async Task OnAfterRenderAsync(bool firstRender)
    {
        if (firstRender)
        {
            LocalOffset = await js.InvokeAsync<int>("getLocalTime");
            LocalTime = DateTime.UtcNow.AddMinutes(-LocalOffset);
            StateHasChanged();
        }

        await base.OnAfterRenderAsync(firstRender);
    }
}

2. Use the DatePicker's HeaderTemplate with a custom TODAY / NOW button. 

3. Hide the NOW button with CSS:

<style>
    .no-now-button .k-time-now {
        display: none;
    }
</style>

<TelerikDateTimePicker @bind-Value="@PickerValue"
                       Format="yyyy-MMM-dd HH:mm:ss"
                       PopupClass="no-now-button"
                       Width="240px" />

@code {
    private DateTime? PickerValue { get; set; }
}

The ability to choose which options to appear in the ContextMenu.

=====

TELERIK EDIT: In the meantime, here is how to hide context menu items with CSS:

    /* Hide the Rename item in the FileManager context menu */
    .k-context-menu:has(.k-svg-i-download) .k-menu-item:nth-of-type(1) {
        display: none;
    }

    /* Hide the Delete item in the FileManager context menu */
    .k-context-menu:has(.k-svg-i-download) .k-menu-item:nth-of-type(3) {
        display: none;
    }

Here is a complete example: https://blazorrepl.telerik.com/cpPkuBEq408A36p010

(Also applies to AutoComplete, DropDownList, MultiSelect, MultiColumnComboBox).

When using Height="auto" in the popup settings and filtering with a dropdown above the component, the dropdown detaches from the main component.

<ComboBoxPopupSettings Height="auto"></ComboBoxPopupSettings>

https://blazorrepl.telerik.com/cKkSQGFO50ovCpr829

A possible workaround is to use a MaxHeight that is less than half the browser viewport.

<ComboBoxPopupSettings Height="auto" MaxHeight="45vh"></ComboBoxPopupSettings>

Support multiple users editing the same content in an editor.

This would be similar to the editor in something like confluence or online Word.

Regards

• The PDF Viewer does not display the initial file if Zoom is set to FitToWidth or FitToPage. This is due to --scale-factor: NaN; --total-scale-factor: NaN; set on the PDF Viewer element.
• If the PDF Viewer initially shows with no loaded file, setting Zoom to FitToWidth or FitToPage initially or after opening a file leads to infinity zoom due to --scale-factor: Infinity; --total-scale-factor: Infinity; set on the PDF Viewer element.

The only scenario that works is to set the initial Zoom to a numeric value and have an open file by default.

I would like a Blazor PropertyGrid with

-- that could be bound to an instance of a custom Type that implemented INotifyPropertyChanged

-- with expandable/collapsible sections with the ability to prevent a  user from expanding a collapsed section (e.g. the user lacks privileges to see that section's data)

-- would keep track of its UI state including collapsed sections (similar to the excellent implementation in Telerik's  Blazor Grid)

-- that would allow the use of all Telerik Blazor editors as cell-value editors

I am interested in using this component primarily as a data-entry UX in a data-entry-intensive line-of-business application.  Such a grid offers standard navigation on all data-entry screens in the application, eliminating tab-order, thereby greatly simplifying the end-user experience. The expanding/collapsing sections make it very economical in its use of screen real-estate. I have used such a component (from a competitor of Telerik) in a WinForms application with excellent results. 

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]

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>

Bug report

Reproduction of the problem

Environment

• Version 15.1.0
• Blazor Server, .NET 10
• Chromium (Chrome and Playwright headless)

Grid ColumnDraggable is never destroyed
In Components/Common/Grid/Rows/TableHeaderRow.cs, Dispose() calls base.Dispose() first, which sets IsDisposed = true. It then calls DestroyColumnDraggable(), which uses InvokeAsync<object>. That method returns early when IsDisposed is true (BaseComponent.InvokeAsync<T>), so destroyColumnDraggable is never sent to the browser. DestroyColumnReorderable() and DestroyColumnResizable() work because they use InvokeVoidAsync, which has no such check.

As a result, every grid with Reorderable="true" or Groupable="true" leaves "<dataId>-telerik-ColumnDraggable" in window.TelerikBlazor._instances. Its draggable.element (the grid's .k-grid-header) keeps the whole disposed page reachable, so the page is never garbage collected.

1. Create two routable pages. Page A has a TelerikGrid with Reorderable="true" and a TelerikTabStrip with a few tabs. Page B is empty.
2. Open Page A, then navigate to Page B with the in-app router (no full reload).
3. Run this in the browser console:

Object.entries(TelerikBlazor._instances)
     .filter(([k, i]) => i && i.element && !i.element.isConnected)
     .map(([k, i]) => k + ' / ' + i.constructor.name)

Sample project attached.

TelerikBlazorApp1.zip

Current behavior

(optional)
one "...-telerik-ColumnDraggable" entry per reorderable or groupable grid, all pointing at detached elements. Each pageA -> pageB round trip adds more, and the detached DOM is never released.

Expected/desired behavior

An empty array is returned. Page A's components were disposed, so their JS instances should have been destroyed.

Workaround

After each navigation, we destroy and remove any registered instance whose element is no longer in the page:

   const instances = window.TelerikBlazor && window.TelerikBlazor._instances;
   for (const key of Object.keys(instances || {})) {
       const i = instances[key];
       if (i && i.element && !i.element.isConnected) {
           try { i.destroy && i.destroy(); } catch (e) { }
           delete instances[key];
       }
   }

Suggested Fix

1. In TableHeaderRow.DestroyColumnDraggable(), use InvokeVoidAsync, as DestroyColumnReorderable() does. Or call the destroy methods before base.Dispose().

Environment

• Kendo/Telerik version:
• Browser: [Chrome XX, Firefox]

Bug report

Reproduction of the problem

(bug report only)
Environment

• Version 15.1.0
• Blazor Server, .NET 10
• Chromium (Chrome and Playwright headless)

TabStrip Tab is never destroyed
Components/TabStrip/Tab.razor.cs registers each tab with initTabStripTab in OnAfterRenderAsync. Its Dispose() only releases the DotNetObjectReference; it never calls InvokeDisposeAsync(). The JS Tab.destroy() method is therefore never called, and TabStrip.destroy() does not destroy its child tabs. Every tab stays in window.TelerikBlazor._instances with its detached <li class="k-tabstrip-item">, which again keeps the disposed page reachable.

1. Create two routable pages. PageA has TabStrip with 3 tabs. PageB is empty.
2. Open PageA, then navigate to PageB with the in-app router (no full reload).
3. Run this in the browser console:

Object.entries(TelerikBlazor._instances)
     .filter(([k, i]) => i && i.element && !i.element.isConnected)
     .map(([k, i]) => k + ' / ' + i.constructor.name)

Sample project attached.

TelerikBlazorApp1.zip

Current behavior

(optional)
One entry per TabStrip tab is returned, all pointing at detached elements. Each pageA -> pageB round trip adds more, and the detached DOM is never released.

Expected/desired behavior

An empty array is returned. PageA's components were disposed, so their JS instances should have been destroyed.

Workaround

After each navigation, we destroy and remove any registered instance whose element is no longer in the page:

const instances = window.TelerikBlazor && window.TelerikBlazor._instances;
   for (const key of Object.keys(instances || {})) {
       const i = instances[key];
       if (i && i.element && !i.element.isConnected) {
           try { i.destroy && i.destroy(); } catch (e) { }
           delete instances[key];
       }
   }

Suggested Fix

1. In Tab.Dispose(), call InvokeDisposeAsync() before base.Dispose(), as TelerikTabStrip.Dispose() does.

Environment

• Kendo/Telerik version:
• Browser: [Chrome XX , Firefox]

I have been trying to improve my Lighthouse score with Google and one of the items it is tagging is the "telerik-blazor.js" file.  I have seen new practices where the JavaScript is imported as needed, see this article here from Microsoft.

Can you please consider this in the future?

===

Telerik edit: A possible workaround is to build the Telerik JavaScript file without some of the components that you don't need.