diff --git a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/App.razor b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/App.razor
index fd5f981b..363c9a67 100644
--- a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/App.razor
+++ b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Components/App.razor
@@ -17,6 +17,7 @@
     <script src="_content/DevExpress.Blazor.Resources/js/preload-script.js"></script>
     <script src="js/typed.umd.js"></script>
     <script src="js/receiver-signature.js?v=9"></script>
+    <script src="js/signflow-theme.js"></script>
     <script src="_framework/blazor.web.js"></script>
 </body>
 
diff --git a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/UserPreferencesController.cs b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/UserPreferencesController.cs
index 47f84b27..4ef2771a 100644
--- a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/UserPreferencesController.cs
+++ b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Controllers/UserPreferencesController.cs
@@ -10,24 +10,37 @@ namespace EnvelopeGenerator.Server.Controllers;
 /// <summary>
 /// Manages per-user UI preferences (theme, dark mode, grid layouts).
 /// Preferences are stored in the distributed cache (dbo.TBDD_CACHE).
+/// Accessible by both Sender and Receiver roles.
 /// </summary>
 [ApiController]
 [Route("api/[controller]")]
-[Authorize(Policy = AuthPolicy.Sender)]
+[Authorize(Policy = AuthPolicy.SenderOrReceiver)]
 public class UserPreferencesController(IUserPreferencesService preferencesService) : ControllerBase
 {
     private static readonly HashSet<string> AllowedThemes =
-        ["blazing-berry", "fluent", "purple"];
+        ["blazing-berry", "blazing-dark", "purple"];
 
     /// <summary>
     /// Returns the current user's UI preferences.
     /// Always returns 200 with defaults if no preferences have been saved yet.
+    /// DisplayName is populated from JWT claims for senders only.
     /// </summary>
     [HttpGet]
     public async Task<ActionResult<UserPreferencesDto>> Get(CancellationToken ct)
     {
-        var username = User.GetUsername();
-        var prefs = await preferencesService.GetAsync(username, ct);
+        bool isReceiver = User.IsReceiver();
+
+        var userId = isReceiver ? User.ReceiverMail() : User.GetUsername();
+
+        if (string.IsNullOrWhiteSpace(userId))
+            return Unauthorized();
+
+        var prefs = await preferencesService.GetOrCreateAsync(userId, ct);
+
+        // Populate DisplayName for sender only (receiver has no given/surname claims)
+        if (!isReceiver)
+            prefs.DisplayName = $"{User.GetPrename()} {User.GetName()}".Trim();
+
         return Ok(prefs);
     }
 
@@ -42,8 +55,12 @@ public class UserPreferencesController(IUserPreferencesService preferencesServic
         if (!AllowedThemes.Contains(dto.ThemeName))
             return BadRequest($"Invalid theme '{dto.ThemeName}'. Allowed: {string.Join(", ", AllowedThemes)}.");
 
-        var username = User.GetUsername();
-        await preferencesService.SaveAsync(username, dto, ct);
+        var userId = User.IsReceiver() ? User.ReceiverMail() : User.GetUsername();
+
+        if (string.IsNullOrWhiteSpace(userId))
+            return Unauthorized();
+
+        await preferencesService.SaveAsync(userId, dto, ct);
         return Ok(dto);
     }
 }
diff --git a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Extensions/ReceiverClaimExtensions.cs b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Extensions/ReceiverClaimExtensions.cs
index cc2611ab..e4b29df9 100644
--- a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Extensions/ReceiverClaimExtensions.cs
+++ b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Extensions/ReceiverClaimExtensions.cs
@@ -1,4 +1,6 @@
 using DigitalData.Auth.Claims;
+using DigitalData.UserManager.Domain.Entities;
+using EnvelopeGenerator.Domain.Constants;
 using Microsoft.IdentityModel.JsonWebTokens;
 using System.Security.Claims;
 
@@ -93,4 +95,14 @@ public static class ReceiverClaimExtensions
         else
             throw new InvalidOperationException($"Claim '{EnvelopeClaimNames.ReceiverId}' is not a valid integer.");
     }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    /// <param name="user"></param>
+    /// <returns></returns>
+    public static bool IsReceiver(this ClaimsPrincipal user)
+    {
+        return Role.Receiver.Authorized.Any(user.IsInRole);
+    }
 }
\ No newline at end of file
diff --git a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Program.cs b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Program.cs
index fc25e496..d8aadebd 100644
--- a/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Program.cs
+++ b/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Program.cs
@@ -271,7 +271,12 @@ try
             .AddAuthenticationSchemes(AuthScheme.Receiver)
             .RequireAuthenticatedUser()
             .RequireRole(Role.Receiver.Full, "receiver"))
-        .AddPolicy(AuthPolicy.ReceiverTFA, policy => policy.RequireRole(Role.Receiver.TFA));
+        .AddPolicy(AuthPolicy.ReceiverTFA, policy => policy.RequireRole(Role.Receiver.TFA))
+        // Combined policy: accepts both Sender and Receiver tokens.
+        // Used by endpoints accessible to both roles (e.g. UserPreferences).
+        .AddPolicy(AuthPolicy.SenderOrReceiver, policy => policy
+            .AddAuthenticationSchemes(AuthScheme.Sender, AuthScheme.Receiver)
+            .RequireAuthenticatedUser());
 
     // User Manager
 #pragma warning disable CS0618