How can I configure multiple debug launch profiles to use distinct appsettings in a Blazor Server App?

The behavior you’re seeing is expected if parts of your startup code rely on the environment name being exactly "Development". By default, many Blazor Server templates use an environment check like this:

CSHARPCopied
if (env.IsDevelopment())
{
    // Enable debugging, detailed errors, etc.
}

When you launch with the https profile, ASPNETCORE_ENVIRONMENT is set to "Development" and the app runs in development mode. When you use your devPK profile, the environment is "DevelopmentPK"; since "DevelopmentPK" ≠ "Development", calls to env.IsDevelopment() return false and configuration that sets up things like your layout (or other developer-only behavior) isn’t executed.

How to Fix It

There are two common approaches:

1. Use the standard "Development" environment when debugging.
   Instead of setting ASPNETCORE_ENVIRONMENT to a custom value, use "Development" and load additional settings from source-specific configuration sections (for example, using custom configuration keys inside appsettings.Development.json).

2. Extend your startup configuration to recognize your custom environment.
   Update your startup (or Program.cs) file to treat "DevelopmentPK" as a development environment. For example:

   CSHARPCopied
   if (env.IsDevelopment() || env.IsEnvironment("DevelopmentPK"))
   {
       // Enable developer features like detailed errors and prerendering
   }

   This way, when you run with the devPK profile, your custom environment is treated like development, and the full layout (including MainLayout.razor) will be rendered.

Summary

The missing header and navigation occur because in the custom environment your startup code does not activate the same configuration that it does in “Development.” By either using “Development” as your environment or updating your startup code to recognize “DevelopmentPK” as a development environment, you can get the intended UI to load.