Escape hatch.

Shogi.UI/Pages/Home/Account/AccountManager.cs

@@ -54,7 +54,7 @@ public class AccountManager
     {
         var state = await authState.GetAuthenticationStateAsync();
 
-        if (state.User?.Identity?.Name == null || state.User?.Identity?.IsAuthenticated == false)
+        if (state?.User?.Identity?.Name == null || state.User?.Identity?.IsAuthenticated == false)
         {
             // Set the login platform so that we know to log in with microsoft after being redirected away from the UI.
             await localStorage.SetAccountPlatform(WhichAccountPlatform.Microsoft);
@@ -66,7 +66,7 @@ public class AccountManager
     /// <summary>
     /// Try to log in with the account used from the previous browser session.
     /// </summary>
-    /// <returns></returns>
+    /// <returns>True if login succeeded.</returns>
     public async Task<bool> TryLoginSilentAsync()
     {
         var platform = await localStorage.GetAccountPlatform();

Shogi.UI/Pages/Home/LoginModal.razor

@@ -1,4 +1,5 @@
 @inject AccountManager Account
+@inject AccountState AccountState
 
 
 <div class="my-modal-background">
@@ -26,13 +27,17 @@
         }
         else
         {
-
             <h1>Welcome to Shogi!</h1>
             <div>
                 <p>How would you like to proceed?</p>
                 <p>
                     <button @onclick="Account.LoginWithMicrosoftAccount">Log in</button>
                     <button @onclick="Account.LoginWithGuestAccount">Proceed as Guest</button>
+                    @if (AccountState.User != null)
+                    {
+                        /* This is an escape hatch in case user login fails in certain ways. */
+                        <button @onclick="Account.LogoutAsync">Logout</button>
+                    }
                 </p>
             </div>
             <p>