Enable hot reload in a Blazor project

Hot reload doesn't work in Blazor project in Visual Studio 2022.

If I set a breakpoint and edit code then I get a message:

The source file has change. It no longer matches the version of the file used to build the application being debugged.

and I have to stop and recompile --- like ASPX.

If I start a new Blazor app in Visual Studio, then hot reload works. So it must be something in my project, not the environment.

I see that somehow

<!-- Visual Studio Browser Link --><script type="text/javascript" src="/_vs/browserLink" async="async" id="__browserLink_initializationData" data-requestId="1d...d" data-requestMappingFromServer="false" data-connectUrl="http://localhost:52084/f74...0/browserLink"></script><!-- End Browser Link --><script src="/_framework/aspnetcore-browser-refresh.js"></script></body></html><!--Blazor-Server-Component-State:CfD...9In0=-->

is being magically added to the HTML source of every page and the Browser Link Dashboad in Visual Studio shows a connection.

Hot reload is not working in my actual project. My project was started from the same template, and hot reload used to work.

I see that these JS files aren't being added to be HTML source, so I guess that's the problem.

I tried copying these into my App.razor but that made no differenct --- still no conneciton in the Browser Link Dashboard.

My launch profiles are identical:

"https": {"commandName": "Project","dotnetRunMessages": true,"launchBrowser": true,"inspectUri": "{wsProtocol}://{url.hostname}:{url.port}/_framework/debug/ws-proxy?browser={browserInspectUri}","applicationUrl": "https://localhost:5202;http://localhost:5292","environmentVariables": {"ASPNETCORE_ENVIRONMENT": "Development"    }  },

In both cases my Program.cs has

builder.Services       .AddRazorComponents()       .AddInteractiveServerComponents()       .AddInteractiveWebAssemblyComponents();

and app.UseWebAssemblyDebugging(); and both InteractiveServer and InteractiveAuto pages work.

Same result if I run from the command line instead of from Visual Studio:

dotnet watch run --project MyProject\MyProject.csproj --launch-profile https

Any ideas what to do?