Overload UriHelper to forceLoad the page even if it's not a Blazor defined Route.

src/Microsoft.AspNetCore.Blazor.Browser.JS/src/Services/UriHelper.ts

@@ -39,9 +39,12 @@ function enableNavigationInterception(assemblyName: string, functionName: string
   window.addEventListener('popstate', handleInternalNavigation);
 }
 
-export function navigateTo(uri: string) {
+export function navigateTo(uri: string, forceLoad: boolean) {
   const absoluteUri = toAbsoluteUri(uri);
-  if (isWithinBaseUriSpace(absoluteUri)) {
+
+  if (forceLoad) {
+    location.href = uri;
+  } else if (isWithinBaseUriSpace(absoluteUri)) {
     performInternalNavigation(absoluteUri);
   } else {
     location.href = uri;

src/Microsoft.AspNetCore.Blazor.Browser/Services/BrowserUriHelper.cs

@@ -47,14 +47,14 @@ protected override void InitializeState()
         }
 
         /// <inheritdoc />
-        protected override void NavigateToCore(string uri)
+        protected override void NavigateToCore(string uri, bool forceLoad)
         {
             if (uri == null)
             {
                 throw new ArgumentNullException(nameof(uri));
             }
 
-            ((IJSInProcessRuntime)JSRuntime.Current).Invoke<object>(Interop.NavigateTo, uri);
+            ((IJSInProcessRuntime)JSRuntime.Current).Invoke<object>(Interop.NavigateTo, uri, forceLoad);
         }
 
         /// <summary>

src/Microsoft.AspNetCore.Blazor.Server/Circuits/RemoteUriHelper.cs

@@ -61,14 +61,10 @@ public static void NotifyLocationChanged(string uriAbsolute)
             uriHelper.TriggerOnLocationChanged();
         }
 
-        /// <summary>
-        /// Navigates to the specified URI.
-        /// </summary>
-        /// <param name="uri">The destination URI. This can be absolute, or relative to the base URI
-        /// (as returned by <see cref="IUriHelper.GetBaseUri"/>).</param>
-        protected override void NavigateToCore(string uri)
+        /// <inheritdoc />
+        protected override void NavigateToCore(string uri, bool forceLoad)
         {
-            _jsRuntime.InvokeAsync<object>(Interop.NavigateTo, uri);
+            _jsRuntime.InvokeAsync<object>(Interop.NavigateTo, uri, forceLoad);
         }
     }
 }

src/Microsoft.AspNetCore.Blazor/Services/IUriHelper.cs

@@ -50,6 +50,7 @@ public interface IUriHelper
         /// </summary>
         /// <param name="uri">The destination URI. This can be absolute, or relative to the base URI
         /// (as returned by <see cref="GetBaseUri"/>).</param>
-        void NavigateTo(string uri);
+        /// <param name="forceLoad">Indicator to force load the URI, even if it's not a blazor route.</param>
+        void NavigateTo(string uri, bool forceLoad = false);
     }
 }

src/Microsoft.AspNetCore.Blazor/Services/UriHelperBase.cs

@@ -44,18 +44,20 @@ public abstract class UriHelperBase : IUriHelper
         /// </summary>
         /// <param name="uri">The destination URI. This can be absolute, or relative to the base URI
         /// (as returned by <see cref="GetBaseUri"/>).</param>
-        public void NavigateTo(string uri)
+        /// <param name="forceLoad">Indicator to force load the URI, even if it's not a blazor route.</param>
+        public void NavigateTo(string uri, bool forceLoad = false)
         {
             EnsureInitialized();
-            NavigateToCore(uri);
+            NavigateToCore(uri, forceLoad);
         }
 
         /// <summary>
         /// Navigates to the specified URI.
         /// </summary>
         /// <param name="uri">The destination URI. This can be absolute, or relative to the base URI
         /// (as returned by <see cref="GetBaseUri"/>).</param>
-        protected abstract void NavigateToCore(string uri);
+        /// <param name="forceLoad">Indicator to force load the URI, even if it's not a blazor route.</param>
+        protected abstract void NavigateToCore(string uri, bool forceLoad);
 
         /// <summary>
         /// Called to initialize BaseURI and current URI before those values the first time.