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1 answer
20 views

Hi,

Is anyone else seeing the following errors generated whenever a Blazor page is closed

[09:31:28 ERR] Unhandled exception in circuit 'SxXtedGLjUhdy-eMLBc7qIlbtXfClIJFypLcSzO9PZs'.
Microsoft.JSInterop.JSDisconnectedException: JavaScript interop calls cannot be issued at this time. This is because the circuit has disconnected and is being disposed.
   at Microsoft.AspNetCore.Components.Server.Circuits.RemoteJSRuntime.BeginInvokeJS(JSInvocationInfo& invocationInfo)
   at Microsoft.JSInterop.JSRuntime.InvokeAsync[TValue](Int64 targetInstanceId, String identifier, JSCallType callType, CancellationToken cancellationToken, Object[] args)
   at Microsoft.JSInterop.JSRuntime.InvokeAsync[TValue](Int64 targetInstanceId, String identifier, JSCallType callType, Object[] args)
   at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync(IJSRuntime jsRuntime, String identifier, Object[] args)
   at Telerik.Blazor.Components.Common.Loader.ComponentLoaderContainer.DisposeAsync()
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.<>c__DisplayClass105_0.<<Dispose>g__HandleAsyncExceptions|0>d.MoveNext()

Claude thinks it is because the ComponentLoaderContainer is missing a try/catch expression around the JSInterop DisposeAsync() call?

Thanks,

Charlotte

Dimo
Telerik team
 answered on 17 Mar 2026
0 answers
20 views

For whatever strange reason it is, my project starts to hit error in string.cs overflow exception after upgrade to 13.0.0.

It is fine when I downgrade it back to 12.3.0.

There are no changes in the code, merely changing the version to 13.0.0 will hit error.

Anybody experiencing this?

 

SHSIOW
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 asked on 13 Mar 2026
1 answer
13 views

When I have a TelerikFilter in a TelerikPopover, removing a group or expression doesn't work. I think the issue is that the filter is not visually updating because when I click the X once nothing happens, but when I click the X again I get the Unhandled Error banner.

I also noticed that if I have another filter using the same variable for Value somewhere else in the DOM (not in a TelerikPopover), then the one in the TelerikPopover works as expected when removing groups and expressions.


<TelerikPopover AnchorSelector="span.filter-popover-target"
                ShowOn="@PopoverShowOn.Click"
                Offset="10" 
                Class="bg-dark-subtle"
                AnimationType="@AnimationType.SlideDown"
                AnimationDuration="500"
                ShowCallout="false"
                Collision="@PopoverCollision.Fit"
                Position="@PopoverPosition.Bottom"
                Width="650px"
                @ref="@FilterPopoverRef">
    <PopoverContent>
        <div p-1>
            <div class="h2">Filter Projects</div>
            <TelerikFilter Value="@ProjectFilter" OnUpdate="@OnFilterUpdate">
                <FilterFields>
                    <FilterField Name="@(nameof(ProjectModel.CustomerContact))"
                                    Type="@(typeof(string))"
                                    Label="Cust Contact"
                                    Operators="@TextFilterOperators" />
                    <FilterField Name="@(nameof(ProjectModel.Description))"
                                    Type="@(typeof(string))"
                                    Label="Description"
                                    Operators="@TextFilterOperators" />
                </FilterFields>
            </TelerikFilter>
        </div>
    </PopoverContent>
</TelerikPopover>

Dimo
Telerik team
 answered on 13 Mar 2026
1 answer
50 views

My project is a windows service that hosts a blazor web site and api.  When deployed using an MSI, Telerik says it is not licensed.  What must be done with the license file to ensure it is registered?

            int portNumber =
                builder.Configuration.GetValue<int>(
                    "Kestrel:Startup:Port");

            builder.Host.UseWindowsService();
            builder.WebHost.UseKestrel(options =>
            {
                options.Listen(IPAddress.Loopback, portNumber);
            });

Joel
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Bronze
 answered on 11 Mar 2026
1 answer
25 views

If I place a breakpoint in the OnUpdate handler (async) in a grid, spend about 20 seconds inspecting values (no code changes, just looking at values) and then "continue" I get the following:

The grid is now completely unresponsive ... it doesn't continue execution and I have to basically stop execution from VS 2026.  Having to return a test session every time I debug is INCREDIBLY time consuming ... there must be a better way to debug?

 

Dimo
Telerik team
 answered on 09 Mar 2026
1 answer
21 views

Hy,

I have an issue with the validation state of a FormItem that uses a custom Template.

I have created the following TelerikForm:

MyForm.razor

DepartmentSelect.razor

LineInefficientyRegistryDto.cs

According with the link Blazor Form Form Items Template - Telerik UI for Blazor, I expect to obtain the following result when the field is not valid after the form submit:

But I have this:

As you can see, the DropDownList is not being highlighted in red. 

Does anyone know why this happens and how to resolve the issue?

Regards,

Marco

 

Dimo
Telerik team
 answered on 05 Mar 2026
1 answer
20 views

I want to use the new DropDownTree component to present a hierarchy of Menus > Tabs > Sections to allow a user to select a preferred default item on initial rendering of the main UI.

I would like to present everything fully expanded and prevent user from collapsing any node.

I furthermore would like to allow the user to only select a "leaf" item - that is, a node with no children.

How can I achieve this?

Dimo
Telerik team
 answered on 05 Mar 2026
1 answer
17 views

I am struggling to get TelerikPdfViewer (version 11.1.1) to render any PDF. The PDF's in question have been validated correct.

<TelerikPdfViewer @ref="@PdfViewerRef" Data="@PdfData" OnError="@OnPdfError" />

The PDF viewer frame is displayed correctly, but no PDF is rendered. Even if I use the toolbar to "open" a PDF, that "opened" PDF does not render. The OnPdfError callback does get called.

protected async Task OnPdfError(PdfViewerErrorEventArgs args) {

}

However args.Message is always null.

Whatever AI and I have tried over several hours has made no difference, and  hopefully someone can suggest what might be stopping it from performing the rendering.

Dimo
Telerik team
 updated answer on 04 Mar 2026
3 answers
705 views
The subject says it...


       <TelerikPdfViewer @ref="@PdfViewerRef"
            Width="100%"
            Height="100%"
            OnDownload="@OnPdfDownload"
            OnError="@OnPdfError"
            OnOpen="@OnPdfOpen"
            Zoom="@PdfZoom"
            ZoomChanged="@OnPdfZoomChanged"
            EnableLoaderContainer="true"
            Data="@PdfData">

            <PdfViewerToolBar>
                <PdfViewerToolBarCustomTool>
                    <TelerikButton OnClick="@PreviousPage">Vorige pagina</TelerikButton>
                    <TelerikButton OnClick="@NextPage">Volgende pagina</TelerikButton>
                </PdfViewerToolBarCustomTool>
                <PdfViewerToolBarZoomTool />
                <PdfViewerToolBarSelectionTool />
                <PdfViewerToolBarSearchTool />
            </PdfViewerToolBar>


        </TelerikPdfViewer>

Dimo
Telerik team
 updated answer on 04 Mar 2026
1 answer
77 views

Hi,

Can I somehow disable the table-resizing functionality in the Editor?
See attached image...

I do not want the resize handles that appears on all table-corners to be inserted at all in the editor html!

Have I missed some simple property or does this have to do with ProseMirror in some way?

Regards
Andreas

Ivan Danchev
Telerik team
 answered on 03 Mar 2026
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