`UseStatusCodePagesWithReExecute` to `not-found` breaks hot reload

[danroth27]

Repro steps:

• Create a default Blazor Web App with .NET 10 RC1
• Run the app using dotnet watch
• Browse to /foo to see the rendered Not Found page
• Edit NotFound.razor and save the change to trigger a Hot Reload

Expected result: The Hot Reloaded changes show up in the browser
Actual result: Browser doesn't update.

If I refresh the Not Found page in the browser the change shows up. But, if I then browse to the Home page and make a change to Home.razor, I also don't see updates on the Home page. If I refresh the Home page in the browser, then the change shows up and Hot Reload then starts work for other pages.

[ilonatommy]

I can reproduce on the blazor server, with daily packs, logs from the run:

dotnet watch
dotnet watch 🔥 Hot reload enabled. For a list of supported edits, see https://aka.ms/dotnet/hot-reload.
dotnet watch 💡 Press Ctrl+R to restart.
dotnet watch 🔨 Building C:\Users\user\Desktop\hotReloadNotFoundIssue\app1\app1.csproj ...
dotnet watch 🔨 Build succeeded: C:\Users\user\Desktop\hotReloadNotFoundIssue\app1\app1.csproj
Using launch settings from C:\Users\user\Desktop\hotReloadNotFoundIssue\app1\Properties\launchSettings.json...
info: Microsoft.Hosting.Lifetime[14]
      Now listening on: http://localhost:5088
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: C:\Users\user\Desktop\hotReloadNotFoundIssue\app1
warn: Microsoft.AspNetCore.HttpsPolicy.HttpsRedirectionMiddleware[3]
      Failed to determine the https port for redirect.
dotnet watch ⌚ File updated: .\Components\Pages\NotFound.razor
dotnet watch 🔥 [app1 (net10.0)] Hot reload succeeded.
dotnet watch ⌚ File updated: .\Components\Pages\Home.razor
dotnet watch 🔥 [app1 (net10.0)] Hot reload succeeded.

The change is not visible even though Hot reload succeeded.. Refresh on the browser or setting DOTNET_WATCH_RESTART_ON_RUDE_EDIT=true loads the change. It does not matter on what .razor file we apply the change.

Working:

• redirect to "not-found" via url bar, change it (hot reaload applied), go to other razor pages, change them (hot reload applied)
• applying changes to any page that we navigated to

Not working:

• any hot reload changes to any file applied after re-execution was caused. We can cause re-execution by navigating to non-existing url e.g. foo.

[javiercn]

TL;DR the browser-refresh script is not getting injected https://github.com/dotnet/sdk/blob/f684b50f80aef16dd1a40055e703801a0da14df1/src/BuiltInTools/BrowserRefresh/ResponseStreamWrapper.cs#L97-L98

It doesn't work after that because the app uses enhanced nav, and that won't inject scripts.

[danroth27]

Makes sense. Is there any reason to restrict the injection by status code? Why not just check the media type?

[ilonatommy]

Makes sense. Is there any reason to restrict the injection by status code? Why not just check the media type?

The restriction was introduced in dotnet/sdk#29152 , @MackinnonBuck do you recall why we decided to filter it?