The sample project WPF_XAMLIslands_v1 cannot publish as self-contained & single file?

[LiLejia]

Clone, build, all file.

However when I try to publish as config above, it failes.

5>Referenced assembly 'UWPApplication, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' does not have a strong name.
5>Referenced assembly 'Helpers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' does not have a strong name.
5>WPF_XAMLIslands_v1 -> C:\Users\henry\source\repos\Xaml-Islands-Samples\Samples\WPF\WPF_XAMLIslands_v1\bin\x64\Debug\netcoreapp3.1\win-x64\WPF_XAMLIslands_v1.dll
5>The "GenerateBundle" task failed unexpectedly.
5>System.ArgumentException: Invalid input specification: Found multiple entries with the same BundleRelativePath
5> at Microsoft.NET.HostModel.Bundle.Bundler.GenerateBundle(IReadOnlyList`1 fileSpecs)
5> at Microsoft.NET.Build.Tasks.GenerateBundle.ExecuteCore()
5> at Microsoft.NET.Build.Tasks.TaskBase.Execute()
5> at Microsoft.NET.Build.Tasks.TaskWithAssemblyResolveHooks.Execute()
5> at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
5> at Microsoft.Build.BackEnd.TaskBuilder.d__26.MoveNext()
========== Build: 4 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========
========== Publish: 0 succeeded, 1 failed, 0 skipped ==========

Any ideas?