It's crashing on .NET 5.0 on Linux!

I've been running .NET Core 3.1 on Ubuntu for a while with Radzen, and upgraded to .NET 5.0

It's working 100% on my Windows development machine.

It's somewhat running on Ubuntu, but Radzen controls aren't showing up properly and are crashing.

You can view live server here

Blazor is working on the first page, click Next, and it shows weird. Click on State or Country dropdown lists and you'll get a crash.

The log shows this

at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle)
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Radzen.DropDownBase`1.OpenPopup(String key, Boolean isFilter, Boolean isFromClick)
at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync(IJSRuntime jsRuntime, String identifier, Object[] args)
at Microsoft.JSInterop.JSRuntime.InvokeAsync[TValue](Int64 targetInstanceId, String identifier, Object[] args)
at e.invokeClientMethod (
at Array.forEach ()
at e.beginInvokeJSFromDotNet (
at new Promise ()
at v (
at e.findFunction (
at Array.forEach ()
Error: Could not find 'Radzen.selectListItem' ('selectListItem' was undefined).
Microsoft.JSInterop.JSException: Could not find 'Radzen.selectListItem' ('selectListItem' was undefined).
Unhandled exception in circuit 'FsFNWmK42U9pDUI4rksOcDfPwINekShXhUFE9PRJMZk'.

Looking at the HTML code-behind, the CSS is loaded in site.css

@import url(../_content/Radzen.Blazor/css/default.css);

The JS is also loading fine

Hi @Hanuman ,
You can attach the source code to check where exactly is the exception.

It's not crashing anywhere specific; that's a client-side crash. It's just failing to show Radzen controls properly. The server-side looks fine.

You misunderstood my advice. You can attach the source code project of Radzen.Blazor components to check why OpenPopup method is raising this exception. The source code is here:

Since it only happens in production, I can't debug the code.

The real error is

Microsoft.JSInterop.JSException: Could not find 'Radzen.selectListItem' ('selectListItem' was undefined).

What could cause JS components to be unrecognized?

Also the visual appearance is missing, indicating a CSS problem. It's as if it wasn't recognizing the CSS and JS files.

One difference between Windows and Linux is file path case-sensitivity, but I don't see how that could be the issue here.

Probably web assets are not being served. Check this thread: Radzen Blazor Components don't respect "custom" environments - #2 by korchev

Ahah! I didn't realize assets in wwwroot had to be copied and updated. It was running on outdated assets.

Now it works thanks :slight_smile: