DotNet.invokeMethodAsync function disabled with .NET 7 RC2 and 8 p5 in a Blazor addin project

[RaoulRSV]

URL of sample

_URl :https://github.com/RaoulRSV/excel-blazor-add-in_NET7.0

Describe the bug

Enabling RC2 disables DotNet.invokeMethodAsync function in a "Blazor addin" project
Edit : I test it also with .NET8.0 pr v5 and I got the same bug wxith a "uncaught reference error : sharedarraybuffer is not defined". Please note that I am using Chrome and Visual Studio 17.7 p2

To Reproduce

Steps to reproduce the behavior:

1. open sample here
2. run sample with NET 7.0.
3. Click twice on "ouvrir" ribbon button
4. check in console message : "fin lancé : 1,2,3" after "lancerchaîné30"
5. in csproj enable : WasmEnableThreads

Expected behavior

_run again : message "fin lancé: 1,2,3" has disappeared (after 2 click on "ouvrir" button") showing that DotNet.invokeMethodAsync function is disabled
Screenshots

If applicable, add screenshots to help explain your problem.

Environment

• Platform [PC desktop,]: ______
• Host [Excel, Word, PowerPoint, etc.]: Excel but could be any ______
• Office version number: ______
• Operating System: windows 11
• Browser (if using Office Online): ______

Additional context

Note that sample is based on "Blazor addin" for which unexpectedly C# break point are not available : see [https://github.com//issues/535]

[pinverso]

@aafvstam , this might be similar to this issue: #512

[RaoulRSV]

This issue seems to apply on all wasm blazor project, be it addin or not. See #548
I suggest this issue to be merged with #548

[RaoulRSV]

as mentioned in #548. I finally understood that multithreading is still not available for blazor, be it with .net 7.0 rc2 or .NET 8.0 preview. I did misinterpret the blogpost on experimental multithreading. It is about webworkers in plain javascript but seems to still have its own difficulties see dotnet/runtime#68162.
Thanks to @aafvstam
I close this issue