A concise guide on setting HTTP response headers when using RazorComponentResult in ASP.NET Core Minimal APIs with Blazor server-rendered components. The post explains why setting headers directly in the endpoint fails (RazorComponentResult controls the full Response lifecycle), and shows the correct approach: injecting IHttpContextAccessor into the Blazor component and setting headers from within the component itself. An extension method is also provided to prevent future mistakes and keep endpoint code clean.
