Blazor WASM ignores the Base Href when trying to fetch hot-reload script

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

The Hot-Reload script ignores the base href when being fetched resulting in a 404 if the base href is set to anything other than /.

Expected Behavior

Debugging with a base href set works as it did in .NET 5.0.

Steps To Reproduce

1. Create a new Blazor WASM application.
2. Change the base href.
3. Attempt to debug the project.
4. The application will fail to load because it fails to find the hot reload script.

• It does not work in both project launch and IIS express launch modes - however in IIS mode you will get the error in the browser, in project launch mode it doesn’t get that far.

See https://github.com/gfs/BlazorWasmHotReloadFailure for an example project that demonstrates this behavior.

Exceptions (if any)

No response

.NET Version

6.0.101

Anything else?

Visual Studio Version 17.0.4

PS C:\Users\gstocco\GitHub\BlazorWasmHotReloadFailure> dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.101
 Commit:    ef49f6213a

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22000
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.101\

Host (useful for support):
  Version: 6.0.1
  Commit:  3a25a7f1cc

.NET SDKs installed:
  6.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 5.0.13 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET runtimes or SDKs:
  https://aka.ms/dotnet-download

[mkArtakMSFT]

We think this is fixed in the upcoming .NET 7 preview 7 release. Can someone please give it a try when it ships and let us know if this is still an issue? Thanks!

[keenam]

@gfs

It’s in the launchSettings.json I will update more info to be clearer.