diff --git a/contrib/Makefile b/contrib/Makefile
index deb55bcc6..5ccf773a1 100644
--- a/contrib/Makefile
+++ b/contrib/Makefile
@@ -14,7 +14,7 @@ reinstall: copy-binaries
 	@echo "💯 backend started"
 
 reinstall-prod:
-	make reinstall APP_INSTALL_ENV= APP_INSTALL_PREFIX= APP_INSTALL_ENV=production
+	make reinstall APP_INSTALL_PREFIX= APP_INSTALL_ENV=production
 
 generated/$(APP_INSTALL_PREFIX)yavscOrg.service:
 generated/$(APP_INSTALL_PREFIX)yavscBlogs.service:
diff --git a/contrib/template.vhost b/contrib/template.vhost
index ea2c2cb6d..b4c9c139e 100644
--- a/contrib/template.vhost
+++ b/contrib/template.vhost
@@ -57,5 +57,25 @@ server {
         proxy_read_timeout 100s;
         proxy_buffering off;
     }
+
+    # SignalR (ChatHub) : WebSocket exige Upgrade/Connection et un timeout
+    # long, sinon la connexion tombe au premier silence ou l'upgrade échoue.
+    # Connection est fixé à "upgrade" (pas de map $connection_upgrade, qui
+    # exigerait une directive map {} globale hors de ce vhost) : SignalR
+    # négocie toujours un upgrade sur ce chemin, et la négociation initiale
+    # (POST /negotiate, sans en-tête Upgrade) n'est pas affectée par cet
+    # en-tête côté Kestrel.
+    location /chathub {
+        proxy_pass         $BACKEND_SCHEME://$HTTP_HOST:$BACKEND_PORT;
+        proxy_http_version 1.1;
+        proxy_set_header   Upgrade $http_upgrade;
+        proxy_set_header   Connection "upgrade";
+        proxy_set_header   Host $host;
+        proxy_set_header   X-Real-IP $remote_addr;
+        proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header   X-Forwarded-Proto $scheme;
+        proxy_read_timeout 3600s;
+        proxy_buffering off;
+    }
     include server-status.conf;
-}
\ No newline at end of file
+}
diff --git a/src/PostIt/PostIt.Android/Properties/AndroidManifest.xml b/src/PostIt/PostIt.Android/Properties/AndroidManifest.xml
index 46f0bc9bb..256555df1 100644
--- a/src/PostIt/PostIt.Android/Properties/AndroidManifest.xml
+++ b/src/PostIt/PostIt.Android/Properties/AndroidManifest.xml
@@ -4,6 +4,7 @@
 		<application
       android:label="PostIt"
       android:icon="@drawable/Icon"
-      android:networkSecurityConfig="@xml/network_security_config">
+			android:networkSecurityConfig="@xml/network_security_config"
+			android:hardwareAccelerated="true">
 	</application>
 </manifest>
diff --git a/src/PostIt/PostIt.Android/Resources/network_security_config.xml b/src/PostIt/PostIt.Android/Resources/xml/network_security_config.xml
similarity index 100%
rename from src/PostIt/PostIt.Android/Resources/network_security_config.xml
rename to src/PostIt/PostIt.Android/Resources/xml/network_security_config.xml
diff --git a/src/PostIt/PostIt.Tests/EstimateEditionPageViewModelTests.cs b/src/PostIt/PostIt.Tests/EstimateEditionPageViewModelTests.cs
index 17efd391b..31c82387d 100644
--- a/src/PostIt/PostIt.Tests/EstimateEditionPageViewModelTests.cs
+++ b/src/PostIt/PostIt.Tests/EstimateEditionPageViewModelTests.cs
@@ -1,4 +1,5 @@
 using System.Net.Http;
+using PostIt.Models;
 using PostIt.ViewModels;
 using Yavsc;
 using Yavsc.Api.Client;
diff --git a/src/PostIt/PostIt.Tests/StatusBarTests.cs b/src/PostIt/PostIt.Tests/StatusBarTests.cs
index 4053dbaf3..15889e0b0 100644
--- a/src/PostIt/PostIt.Tests/StatusBarTests.cs
+++ b/src/PostIt/PostIt.Tests/StatusBarTests.cs
@@ -2,6 +2,7 @@ using Avalonia.Controls;
 using Avalonia.Headless.XUnit;
 using Avalonia.VisualTree;
 using PostIt.Controls;
+using PostIt.Models;
 using PostIt.ViewModels;
 
 namespace PostIt.Tests;
@@ -21,7 +22,9 @@ public class StatusBarTests
     [AvaloniaFact]
     public void Status_message_is_rendered_by_a_SelectableTextBlock()
     {
-        var bar = new StatusBar { DataContext = StatusNotice.Error("Échec de la suppression : boom") };
+        var bar = new StatusBar {
+            DataContext =
+            StatusNotice.Error("Échec de la suppression : boom") };
         var window = new Window { Content = bar };
         window.Show();
 
@@ -32,4 +35,4 @@ public class StatusBarTests
         Assert.NotNull(message);
         Assert.Equal("Échec de la suppression : boom", message!.Text);
     }
-}
\ No newline at end of file
+}
diff --git a/src/PostIt/PostIt/Controls/StatusBar.axaml b/src/PostIt/PostIt/Controls/StatusBar.axaml
index 2f46fee33..b279ce5ea 100644
--- a/src/PostIt/PostIt/Controls/StatusBar.axaml
+++ b/src/PostIt/PostIt/Controls/StatusBar.axaml
@@ -10,16 +10,18 @@
             Padding="8">
         <StackPanel Orientation="Horizontal" Spacing="8">
             <TextBlock Text="{Binding Glyph}"
-                       FontWeight="Bold"
-                       Foreground="{Binding Foreground}"
-                       VerticalAlignment="Top"/>
-            <!-- SelectableTextBlock so the user can select + copy the
-                 status message (TextBlock is not selectable in
-                 Avalonia). Keeps Text/TextWrapping/Foreground. -->
+              FontWeight="Bold"
+              Foreground="{Binding Foreground}"
+              VerticalAlignment="Top"/>
             <SelectableTextBlock Text="{Binding Message}"
-                       Foreground="{Binding Foreground}"
-                       TextWrapping="Wrap"
-                       VerticalAlignment="Center"/>
+              Foreground="{Binding Foreground}"
+              TextWrapping="Wrap"
+              VerticalAlignment="Center"/>
+            <Button Content="{Binding CheckCommandLabel}"
+                    VerticalAlignment="Center"
+                    IsVisible="{Binding HasCheckCommand}"
+                    Command="{Binding CheckCommand}"
+                    />
         </StackPanel>
     </Border>
 </UserControl>
diff --git a/src/PostIt/PostIt/Models/ChatMessageDto.cs b/src/PostIt/PostIt/Models/ChatMessageDto.cs
new file mode 100644
index 000000000..b93ccbe29
--- /dev/null
+++ b/src/PostIt/PostIt/Models/ChatMessageDto.cs
@@ -0,0 +1,14 @@
+namespace PostIt.ViewModels.Chat
+{
+    /// <summary>
+    /// DTO minimal calqué sur l'objet anonyme émis par le hub
+    /// (<c>{ Name, Room, Message }</c>) via l'événement
+    /// <c>ReceiveMessage</c>.
+    /// </summary>
+    public class ChatMessageDto
+    {
+        public string? Name { get; set; }
+        public string? Room { get; set; }
+        public string? Message { get; set; }
+    }
+}
diff --git a/src/PostIt/PostIt/Models/ChatRoomInfo.cs b/src/PostIt/PostIt/Models/ChatRoomInfo.cs
new file mode 100644
index 000000000..548371157
--- /dev/null
+++ b/src/PostIt/PostIt/Models/ChatRoomInfo.cs
@@ -0,0 +1,11 @@
+using System.Collections.Generic;
+
+namespace PostIt.ViewModels.Chat
+{
+    // DTO minimal calqué sur votre logique serveur ChatRoomInfo
+    public class ChatRoomInfo
+    {
+        public string? Name { get; set; }
+        public List<string> Users { get; set; } = new();
+    }
+}
diff --git a/src/PostIt/PostIt/Models/IWithLabel.cs b/src/PostIt/PostIt/Models/IWithLabel.cs
new file mode 100644
index 000000000..b76f912db
--- /dev/null
+++ b/src/PostIt/PostIt/Models/IWithLabel.cs
@@ -0,0 +1,6 @@
+namespace PostIt.ViewModels;
+
+internal interface IWithLabel
+{
+    string Label { get; }
+}
diff --git a/src/PostIt/PostIt/Models/StatusNotice.cs b/src/PostIt/PostIt/Models/StatusNotice.cs
deleted file mode 100644
index c50ac3503..000000000
--- a/src/PostIt/PostIt/Models/StatusNotice.cs
+++ /dev/null
@@ -1,35 +0,0 @@
-namespace PostIt.ViewModels;
-
-public enum StatusSeverity
-{
-    Info,
-    Warning,
-    Error
-}
-
-public sealed class StatusNotice
-{
-    public string Message { get; }
-    public StatusSeverity Severity { get; }
-    public string Glyph { get; }
-    public string Background { get; }
-    public string BorderBrush { get; }
-    public string Foreground { get; }
-
-    public StatusNotice(string message, StatusSeverity severity)
-    {
-        Message = string.IsNullOrWhiteSpace(message) ? "Pret." : message;
-        Severity = severity;
-
-        (Glyph, Background, BorderBrush, Foreground) = severity switch
-        {
-            StatusSeverity.Error => ("!", "#7F1D1D", "#C62828", "#e1f0f6"),
-            StatusSeverity.Warning => ("~", "#7C4A03", "#E6A700", "#eaeaea"),
-            _ => ("i", "#E8F0FE", "#5B8DEF", "#1E3A8A"),
-        };
-    }
-
-    public static StatusNotice Info(string message) => new(message, StatusSeverity.Info);
-    public static StatusNotice Warning(string message) => new(message, StatusSeverity.Warning);
-    public static StatusNotice Error(string message) => new(message, StatusSeverity.Error);
-}
diff --git a/src/PostIt/PostIt/Models/StatusSeverity.cs b/src/PostIt/PostIt/Models/StatusSeverity.cs
new file mode 100644
index 000000000..eb6ef4502
--- /dev/null
+++ b/src/PostIt/PostIt/Models/StatusSeverity.cs
@@ -0,0 +1,8 @@
+namespace PostIt.Models;
+
+public enum StatusSeverity
+{
+    Info,
+    Warning,
+    Error
+}
diff --git a/src/PostIt/PostIt/ViewModels/ACL/CirclesPageViewModel.cs b/src/PostIt/PostIt/ViewModels/ACL/CirclesPageViewModel.cs
index cd068b4f4..6201c061b 100644
--- a/src/PostIt/PostIt/ViewModels/ACL/CirclesPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/ACL/CirclesPageViewModel.cs
@@ -5,7 +5,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using Microsoft.Extensions.DependencyInjection;
-using PostIt.Helpers;
+using PostIt.Models;
 using PostIt.Services;
 using Yavsc.Api.Client;
 using Yavsc.Api.Client.Dtos;
diff --git a/src/PostIt/PostIt/ViewModels/ACL/PostAclDialogViewModel.cs b/src/PostIt/PostIt/ViewModels/ACL/PostAclDialogViewModel.cs
index be1b220fa..43ed60823 100644
--- a/src/PostIt/PostIt/ViewModels/ACL/PostAclDialogViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/ACL/PostAclDialogViewModel.cs
@@ -12,6 +12,7 @@ using Yavsc.Api.Client.Dtos;
 using Yavsc.Abstract.BlogSpot;
 using Yavsc.Abstract.Identity.Security;
 using System.Net.Http;
+using PostIt.Models;
 
 namespace PostIt.ViewModels;
 
diff --git a/src/PostIt/PostIt/ViewModels/Activity/ActivitiesPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/ActivitiesPageViewModel.cs
index bd13faf9b..1890309ec 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/ActivitiesPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/ActivitiesPageViewModel.cs
@@ -8,6 +8,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Helpers;
+using PostIt.Models;
 using Yavsc.Abstract.Workflow;
 using Yavsc.Api.Client;
 
diff --git a/src/PostIt/PostIt/ViewModels/Activity/BillingQueriesPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/BillingQueriesPageViewModel.cs
index f1b05b749..5cd373708 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/BillingQueriesPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/BillingQueriesPageViewModel.cs
@@ -12,6 +12,7 @@ using PostIt.Helpers;
 using Yavsc;
 using Yavsc.Api.Client;
 using Yavsc.Abstract.Workflow;
+using PostIt.Models;
 
 namespace PostIt.ViewModels;
 
diff --git a/src/PostIt/PostIt/ViewModels/Activity/BillingQueryDetailsPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/BillingQueryDetailsPageViewModel.cs
index c9f122dce..0df05b21a 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/BillingQueryDetailsPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/BillingQueryDetailsPageViewModel.cs
@@ -388,4 +388,4 @@ public partial class BillingQueryDetailsPageViewModel : ViewModelBase, IActionSt
             QueryStatus.Success => "V",
             _ => "i",
         };
-}
\ No newline at end of file
+}
diff --git a/src/PostIt/PostIt/ViewModels/Activity/CommandFormsPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/CommandFormsPageViewModel.cs
index 533fbc380..14e7e74b9 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/CommandFormsPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/CommandFormsPageViewModel.cs
@@ -6,6 +6,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Helpers;
+using PostIt.Models;
 using Yavsc.Abstract.Workflow;
 using Yavsc.Api.Client;
 
diff --git a/src/PostIt/PostIt/ViewModels/Activity/EstimateEditionPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/EstimateEditionPageViewModel.cs
index 1f1e4b4be..f8f94436a 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/EstimateEditionPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/EstimateEditionPageViewModel.cs
@@ -10,6 +10,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Helpers;
+using PostIt.Models;
 using Yavsc.Api.Client;
 
 namespace PostIt.ViewModels;
diff --git a/src/PostIt/PostIt/ViewModels/Activity/EstimateListPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/EstimateListPageViewModel.cs
index c90a6d884..766dda903 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/EstimateListPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/EstimateListPageViewModel.cs
@@ -9,6 +9,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Helpers;
+using PostIt.Models;
 using Yavsc.Api.Client;
 
 namespace PostIt.ViewModels;
diff --git a/src/PostIt/PostIt/ViewModels/Activity/ProviderOngoingRequestsPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Activity/ProviderOngoingRequestsPageViewModel.cs
index 7fd84fd88..360bf54ad 100644
--- a/src/PostIt/PostIt/ViewModels/Activity/ProviderOngoingRequestsPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Activity/ProviderOngoingRequestsPageViewModel.cs
@@ -13,6 +13,7 @@ using PostIt.Helpers;
 using Yavsc;
 using Yavsc.Abstract.Workflow;
 using Yavsc.Api.Client;
+using PostIt.Models;
 
 namespace PostIt.ViewModels;
 
diff --git a/src/PostIt/PostIt/ViewModels/Blogs/BlogsViewModel.cs b/src/PostIt/PostIt/ViewModels/Blogs/BlogsViewModel.cs
index a1e016e7f..6fe6eccc9 100644
--- a/src/PostIt/PostIt/ViewModels/Blogs/BlogsViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Blogs/BlogsViewModel.cs
@@ -12,6 +12,7 @@ using Yavsc.Api.Client;
 using Yavsc.Abstract.Files;
 using PostIt.Helpers;
 using AvaloniaEdit.Document;
+using PostIt.Models;
 
 namespace PostIt.ViewModels;
 
diff --git a/src/PostIt/PostIt/ViewModels/Chat/ChatViewModel.cs b/src/PostIt/PostIt/ViewModels/Chat/ChatViewModel.cs
index 8a70b507d..e72f07655 100644
--- a/src/PostIt/PostIt/ViewModels/Chat/ChatViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Chat/ChatViewModel.cs
@@ -4,18 +4,37 @@ using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using Microsoft.AspNetCore.SignalR.Client;
+using Microsoft.Extensions.DependencyInjection;
+using PostIt.Models;
+using PostIt.Services;
+using Yavsc;
 
 namespace PostIt.ViewModels.Chat
 {
+    /// <summary>
+    /// ViewModel pour la gestion du chat,
+    /// incluant la connexion au Hub SignalR,
+    /// la gestion des salons et des utilisateurs connectés.
+    /// </summary>
 
     public partial class ChatViewModel : ViewModelBase
     {
+        private readonly Settings _settings;
+        private readonly YavscApiClient? _api;
+
+        // Le paramètre optionnel permet l'instanciation design-time
+        // (Design.DataContext dans ChatPage.axaml) sans conteneur DI.
+        public ChatViewModel(YavscApiClient? api = null)
+        {
+            var app = App.Current as App;
+            _settings = app!.ServiceProvider!.GetRequiredService<Settings>(); // Assurez-vous que _settings est initialisé avant utilisation.
+            _api = api;
+            Status = new StatusNotice("Déconnecté", StatusSeverity.Info,
+            new RelayCheckCommand("Connecter", async () => await ConnectAsync()));
+        }
+
         private HubConnection? _connection;
 
-        [ObservableProperty]
-        public partial string ServerUrl { get; protected set; } = "https://yavsc.pschneider.fr/chathub";
-
-
         [ObservableProperty]
         public partial string CurrentRoom { get; set; } =  "General";
 
@@ -24,7 +43,6 @@ namespace PostIt.ViewModels.Chat
 
         [ObservableProperty]
         public partial StatusNotice Status { get; set; }
-                = new StatusNotice("Déconnecté", StatusSeverity.Info);
 
         [ObservableProperty]
         public partial bool IsConnected { get; set; } = false;
@@ -40,20 +58,61 @@ namespace PostIt.ViewModels.Chat
         [RelayCommand]
         public async Task JoinRoomCommand() => await JoinRoomAsync();
 
-        [RelayCommand]
-        public async Task ChangeNickCommand() => await ChangeNickAsync();
-
         public override bool CanNavigateNext { get; protected set; } = false;
         public override bool CanNavigatePrevious { get; protected set; } = true;
 
+        private async Task DisconnectAsync()
+        {
+            if (_connection != null)
+            {
+                await _connection.StopAsync();
+                await _connection.DisposeAsync();
+                _connection = null;
+            }
+            IsConnected = false;
+            Status = new StatusNotice("Déconnecté", StatusSeverity.Info,
+             new RelayCheckCommand("Connecter", async () => await ConnectAsync()));
+        }
+
         private async Task ConnectAsync()
         {
             try
             {
-                Status = new StatusNotice("Connexion en cours...", StatusSeverity.Info);
+                Status = new StatusNotice("Connexion en cours...", StatusSeverity.Info,
+                 new RelayCheckCommand("Vérifier la connexion", async () => await CheckConnectionAsync()));
+
+                if (_api == null || !_api.HasValidSession)
+                {
+                    Status = new StatusNotice("Session expirée : reconnectez-vous avant d'ouvrir le chat.", StatusSeverity.Error,
+                    new RelayCheckCommand("Reconnecter", async () => await ConnectAsync()));
+                    return;
+                }
+
+                // Le hub est mappé à la racine du service ("/chathub"),
+                // pas sous le préfixe versionné "/api/v1" : on le retire.
+                var hubBase = _settings.ApiUrl.TrimEnd('/');
+                if (hubBase.EndsWith("/api/v1", StringComparison.OrdinalIgnoreCase))
+                    hubBase = hubBase[..^"/api/v1".Length];
+                var hubUrl = hubBase + "/" + Constants.ChatHubPath;
 
                 _connection = new HubConnectionBuilder()
-                    .WithUrl(ServerUrl)
+                    .WithUrl(hubUrl,
+
+                    options =>
+                    {
+                        // Le hub est [Authorize] : on attache le Bearer OIDC.
+                        // AccessTokenProvider est rappelé à chaque reconnexion,
+                        // donc on tente un refresh silencieux à chaque appel.
+                        // Un refresh mort (invalid_grant) ne doit pas faire
+                        // échouer StartAsync avec une exception interne : on
+                        // renvoie le token courant (éventuellement expiré) et
+                        // le serveur répondra un 401 propre, surfacé à l'UI.
+                        options.AccessTokenProvider = async () =>
+                        {
+                            await _api.TrySilentLoginAsync();
+                            return _api.CurrentAccessToken;
+                        };
+                    })
                     .WithAutomaticReconnect()
                     .Build();
 
@@ -88,15 +147,20 @@ namespace PostIt.ViewModels.Chat
 
                 await _connection.StartAsync();
                 IsConnected = true;
-                Status = new StatusNotice("Connecté au Hub SignalR", StatusSeverity.Info);
+                Status = new StatusNotice("Connecté au Hub SignalR", StatusSeverity.Info, new RelayCheckCommand("Déconnecter", async () => await DisconnectAsync()));
             }
             catch (Exception ex)
             {
-                Status = new StatusNotice($"Erreur : {ex.Message}", StatusSeverity.Error);
+                Status = new StatusNotice($"Erreur : {ex.Message}", StatusSeverity.Error, new RelayCheckCommand("Reconnecter", async () => await ConnectAsync()));
                 IsConnected = false;
             }
         }
 
+        private async Task CheckConnectionAsync()
+        {
+            throw new NotImplementedException();
+        }
+
         private async Task JoinRoomAsync()
         {
             if (_connection == null || string.IsNullOrWhiteSpace(CurrentRoom)) return;
@@ -115,21 +179,5 @@ namespace PostIt.ViewModels.Chat
                 Messages.Add($"Erreur Join: {ex.Message}");
             }
         }
-
-        private async Task ChangeNickAsync()
-        {
-            if (_connection == null || string.IsNullOrWhiteSpace(NickName)) return;
-
-            try
-            {
-                // Appel de la méthode publique 'Nick' du Hub (void)
-                await _connection.InvokeAsync("Nick", NickName);
-                Messages.Add($"Demande de changement de pseudo vers '{NickName}' envoyée.");
-            }
-            catch (Exception ex)
-            {
-                Messages.Add($"Erreur Nick: {ex.Message}");
-            }
-        }
     }
 }
diff --git a/src/PostIt/PostIt/ViewModels/Chat/RelayCheckCommand.cs b/src/PostIt/PostIt/ViewModels/Chat/RelayCheckCommand.cs
new file mode 100644
index 000000000..909d7a859
--- /dev/null
+++ b/src/PostIt/PostIt/ViewModels/Chat/RelayCheckCommand.cs
@@ -0,0 +1,33 @@
+using System;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace PostIt.ViewModels.Chat
+{
+    internal class RelayCheckCommand : ICommand, IWithLabel
+    {
+        public string Label { get; }
+        private Func<Task> value;
+
+        public RelayCheckCommand(string v, Func<Task> value)
+        {
+            this.Label = v;
+            this.value = value;
+        }
+
+        public event EventHandler? CanExecuteChanged;
+
+        public bool CanExecute(object? parameter)
+        {
+            return value != null;
+        }
+
+        public void Execute(object? parameter)
+        {
+            if (value != null)
+            {
+                _ = value();
+            }
+        }
+    }
+}
diff --git a/src/PostIt/PostIt/ViewModels/Commands/BillingCommandPageViewModel.cs b/src/PostIt/PostIt/ViewModels/Commands/BillingCommandPageViewModel.cs
index 5ad2b08f4..4898c9560 100644
--- a/src/PostIt/PostIt/ViewModels/Commands/BillingCommandPageViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Commands/BillingCommandPageViewModel.cs
@@ -2,6 +2,7 @@ using System;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using PostIt.Models;
 using Yavsc;
 using Yavsc.Abstract.Workflow;
 using Yavsc.Api.Client;
diff --git a/src/PostIt/PostIt/ViewModels/Commands/BrushViewModel.cs b/src/PostIt/PostIt/ViewModels/Commands/BrushViewModel.cs
index 72d9ce8ea..1b1847e96 100644
--- a/src/PostIt/PostIt/ViewModels/Commands/BrushViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/Commands/BrushViewModel.cs
@@ -6,6 +6,7 @@ using System.Net;
 using System.Net.Http;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
+using PostIt.Models;
 using Yavsc.Abstract.Workflow;
 using Yavsc.Api.Client;
 using Yavsc.Models.Billing;
diff --git a/src/PostIt/PostIt/ViewModels/Layout/ActionStatusViewModelExtensions.cs b/src/PostIt/PostIt/ViewModels/Layout/ActionStatusViewModelExtensions.cs
index 614d477c8..9fe286ac0 100644
--- a/src/PostIt/PostIt/ViewModels/Layout/ActionStatusViewModelExtensions.cs
+++ b/src/PostIt/PostIt/ViewModels/Layout/ActionStatusViewModelExtensions.cs
@@ -1,3 +1,5 @@
+using PostIt.Models;
+
 namespace PostIt.ViewModels;
 
 public interface IActionStatusViewModel
@@ -29,4 +31,4 @@ public static class ActionStatusViewModelExtensions
             _ => StatusNotice.Info(normalizedMessage),
         };
     }
-}
\ No newline at end of file
+}
diff --git a/src/PostIt/PostIt/ViewModels/MyFiles/MyFilesViewModel.cs b/src/PostIt/PostIt/ViewModels/MyFiles/MyFilesViewModel.cs
index cc4b46828..169b29b16 100644
--- a/src/PostIt/PostIt/ViewModels/MyFiles/MyFilesViewModel.cs
+++ b/src/PostIt/PostIt/ViewModels/MyFiles/MyFilesViewModel.cs
@@ -7,6 +7,7 @@ using Avalonia;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using PostIt.Helpers;
+using PostIt.Models;
 using Yavsc.Api.Client;
 
 namespace PostIt.ViewModels;
@@ -226,4 +227,4 @@ public partial class MyFilesViewModel : ViewModelBase, IActionStatusViewModel
         var idx = current.LastIndexOf('/');
         return idx < 0 ? string.Empty : current[..idx];
     }
-}
\ No newline at end of file
+}
diff --git a/src/PostIt/PostIt/ViewModels/Settings/Settings.cs b/src/PostIt/PostIt/ViewModels/Settings/Settings.cs
index c034437b8..72eea5d35 100644
--- a/src/PostIt/PostIt/ViewModels/Settings/Settings.cs
+++ b/src/PostIt/PostIt/ViewModels/Settings/Settings.cs
@@ -9,6 +9,7 @@ using System.Net.Http;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Globalization;
+using PostIt.Models;
 
 [assembly: InternalsVisibleTo("PostIt.Tests")]
 
diff --git a/src/PostIt/PostIt/ViewModels/StatusNotice.cs b/src/PostIt/PostIt/ViewModels/StatusNotice.cs
new file mode 100644
index 000000000..a14f1a87b
--- /dev/null
+++ b/src/PostIt/PostIt/ViewModels/StatusNotice.cs
@@ -0,0 +1,43 @@
+using System.Windows.Input;
+using PostIt.Models;
+
+namespace PostIt.ViewModels;
+
+public sealed class StatusNotice
+{
+    public string Message { get; }
+    public StatusSeverity Severity { get; }
+    public string Glyph { get; }
+    public string Background { get; }
+    public string BorderBrush { get; }
+    public string Foreground { get; }
+
+    public bool HasCheckCommand { get; }
+
+    public ICommand? CheckCommand { get; }
+
+    public string CheckCommandLabel { get; }
+
+    public StatusNotice(string message, StatusSeverity severity, ICommand? checkCommand)
+    {
+        Message = string.IsNullOrWhiteSpace(message) ? "Pret." : message;
+        Severity = severity;
+
+        (Glyph, Background, BorderBrush, Foreground) = severity switch
+        {
+            StatusSeverity.Error => ("!", "#7F1D1D", "#C62828", "#e1f0f6"),
+            StatusSeverity.Warning => ("~", "#7C4A03", "#E6A700", "#eaeaea"),
+            _ => ("i", "#E8F0FE", "#5B8DEF", "#1E3A8A"),
+        };
+        HasCheckCommand = checkCommand != null;
+        CheckCommand = checkCommand;
+        CheckCommandLabel = HasCheckCommand ? "Check" :
+            checkCommand == null ?
+                string.Empty :
+                checkCommand is IWithLabel labeled ? labeled.Label : string.Empty;
+    }
+
+    public static StatusNotice Info(string message, ICommand? checkCommand = null) => new(message, StatusSeverity.Info, checkCommand);
+    public static StatusNotice Warning(string message, ICommand? checkCommand = null) => new(message, StatusSeverity.Warning, checkCommand);
+    public static StatusNotice Error(string message, ICommand? checkCommand = null) => new(message, StatusSeverity.Error, checkCommand);
+}
diff --git a/src/PostIt/PostIt/Views/Chat/ChatPage.axaml b/src/PostIt/PostIt/Views/Chat/ChatPage.axaml
index 0ac7e818c..55251f544 100644
--- a/src/PostIt/PostIt/Views/Chat/ChatPage.axaml
+++ b/src/PostIt/PostIt/Views/Chat/ChatPage.axaml
@@ -1,4 +1,5 @@
 <ContentPage
+  x:Class="PostIt.Views.Chat.ChatPage"
   xmlns="https://github.com/avaloniaui"
   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   xmlns:AvaloniaEdit="clr-namespace:AvaloniaEdit;assembly=AvaloniaEdit"
@@ -9,38 +10,71 @@
   xmlns:postitControls="using:PostIt.Controls"
   xmlns:views="using:PostIt.Views.Chat"
   xmlns:vm="using:PostIt.ViewModels.Chat"
-  x:Class="PostIt.Views.Chat.ChatPage"
-  x:DataType="vm:ChatViewModel" >
+  x:DataType="vm:ChatViewModel"
+  >
+  <Design.DataContext>
+    <vm:ChatViewModel />
+  </Design.DataContext>
 
-    <Grid RowDefinitions="Auto, *, Auto" Margin="10">
+  <Grid Margin="10" RowDefinitions="Auto, *, Auto">
 
-        <Grid Grid.Row="1" ColumnDefinitions="*, 200" Margin="0,0,0,10">
+    <Grid
+      Grid.Row="1"
+      Margin="0,0,0,10"
+      ColumnDefinitions="*, 200">
 
-            <!-- Journal des flux de messages & notifications -->
-            <Grid Grid.Column="0" RowDefinitions="Auto, *">
-                <StackPanel Grid.Row="0" Orientation="Horizontal" Spacing="10" Margin="0,0,0,5">
-                    <TextBox Text="{Binding CurrentRoom}" Watermark="Nom du salon" Width="200" VerticalAlignment="Center"/>
-                    <Button Content="Rejoindre Salon (Join)" Command="{Binding JoinRoomCommand}"/>
-                </StackPanel>
+      <!--  Journal des flux de messages & notifications  -->
+      <Grid Grid.Column="0" RowDefinitions="Auto, *">
+        <StackPanel
+          Grid.Row="0"
+          Margin="0,0,0,5"
+          Orientation="Horizontal"
+          Spacing="10">
+          <TextBox
+            Width="200"
+            VerticalAlignment="Center"
+            Text="{Binding CurrentRoom}"
+            PlaceholderText="Nom du salon" />
+          <Button Command="{Binding JoinRoomCommand}" Content="Rejoindre Salon (Join)" />
+        </StackPanel>
 
-                <ListBox Grid.Row="1" ItemsSource="{Binding Messages}"  BorderBrush="#E0E0E0" BorderThickness="1">
-                    <ListBox.ItemTemplate>
-                        <DataTemplate>
-                            <TextBlock Text="{Binding}" TextWrapping="Wrap"/>
-                        </DataTemplate>
-                    </ListBox.ItemTemplate>
-                </ListBox>
-            </Grid>
+        <ListBox
+          Grid.Row="1"
+          BorderBrush="#E0E0E0"
+          BorderThickness="1"
+          ItemsSource="{Binding Messages}">
+          <ListBox.ItemTemplate>
+            <DataTemplate>
+              <TextBlock Text="{Binding}" TextWrapping="Wrap" />
+            </DataTemplate>
+          </ListBox.ItemTemplate>
+        </ListBox>
+      </Grid>
 
-            <!-- Liste des utilisateurs présents (MàJ via l'événement 'joint') -->
-            <Border Grid.Column="1" Margin="10,0,0,0" BorderBrush="#E0E0E0" BorderThickness="1" >
-                <Grid RowDefinitions="Auto, *">
-                    <TextBlock Grid.Row="0" Text="Membres Présents" FontWeight="Bold" Margin="5" HorizontalAlignment="Center"/>
-                    <ListBox Grid.Row="1" ItemsSource="{Binding ConnectedUsers}" BorderThickness="0"/>
-                </Grid>
-            </Border>
+      <!--  Liste des utilisateurs présents (MàJ via l'événement 'joint')  -->
+      <Border
+        Grid.Column="1"
+        Margin="10,0,0,0"
+        BorderBrush="#E0E0E0"
+        BorderThickness="1">
+        <Grid RowDefinitions="Auto, *">
+          <TextBlock
+            Grid.Row="0"
+            Margin="5"
+            HorizontalAlignment="Center"
+            FontWeight="Bold"
+            Text="Membres Présents" />
+          <ListBox
+            Grid.Row="1"
+            BorderThickness="0"
+            ItemsSource="{Binding ConnectedUsers}" />
         </Grid>
-        <postitControls:StatusBar Grid.Row="4" DataContext="{Binding Status}" x:Name="StatusBar" />
-
+      </Border>
     </Grid>
+    <postitControls:StatusBar
+      x:Name="StatusBar"
+      Grid.Row="4"
+      DataContext="{Binding Status}" />
+
+  </Grid>
 </ContentPage>
diff --git a/src/PostIt/PostIt/Views/Chat/ChatPage.axaml.cs b/src/PostIt/PostIt/Views/Chat/ChatPage.axaml.cs
index 5be61b86c..f73e1f827 100644
--- a/src/PostIt/PostIt/Views/Chat/ChatPage.axaml.cs
+++ b/src/PostIt/PostIt/Views/Chat/ChatPage.axaml.cs
@@ -7,4 +7,5 @@ public partial class ChatPage : ContentPage
     {
         InitializeComponent();
     }
+
 }
diff --git a/src/PostIt/PostIt/Views/Layout/MainView.axaml b/src/PostIt/PostIt/Views/Layout/MainView.axaml
index 92f53eb54..94b1d98bc 100644
--- a/src/PostIt/PostIt/Views/Layout/MainView.axaml
+++ b/src/PostIt/PostIt/Views/Layout/MainView.axaml
@@ -16,6 +16,7 @@
   <DockPanel LastChildFill="True">
     <views:SessionStatusBanner
       x:Name="SessionBanner"
+      DataContext="{Binding SessionStatus}"
       DockPanel.Dock="Bottom"/>
     <NavigationPage x:Name="NavRoot"/>
   </DockPanel>
diff --git a/src/PostIt/PostIt/Views/Layout/SettingsPage.axaml.cs b/src/PostIt/PostIt/Views/Layout/SettingsPage.axaml.cs
index b50245919..9df94960d 100644
--- a/src/PostIt/PostIt/Views/Layout/SettingsPage.axaml.cs
+++ b/src/PostIt/PostIt/Views/Layout/SettingsPage.axaml.cs
@@ -8,6 +8,7 @@ using System.Threading.Tasks;
 using Avalonia.Controls;
 using Avalonia.Platform.Storage;
 using Microsoft.Extensions.DependencyInjection;
+using PostIt.Models;
 using PostIt.Services;
 using PostIt.ViewModels;
 
diff --git a/src/Yavsc.Abstract/Chat/ChatHubConstants.cs b/src/Yavsc.Abstract/Chat/ChatHubConstants.cs
index c673e6fae..e51e77e63 100644
--- a/src/Yavsc.Abstract/Chat/ChatHubConstants.cs
+++ b/src/Yavsc.Abstract/Chat/ChatHubConstants.cs
@@ -4,10 +4,8 @@ namespace Yavsc.Abstract.Chat
 {
     public static class ChatHubConstants
     {
-        public const string HubGroupAuthenticated = "authenticated";
-        public const string HubGroupAnonymous = "anonymous";
         public const string HubGroupCops= "cops";
-        public const string HubGroupRomsPrefix = "room_";
+        public const string HubGroupRoomsPrefix = "room_";
         public const int MaxChanelName = 255;
 
         public const string HubGroupFollowingPrefix = "fol ";
@@ -21,6 +19,6 @@ namespace Yavsc.Abstract.Chat
         public const string HopWontKickOp  = "Half operator cannot kick any operator";
         public const string LabAuthChatUser  = "Authenticated chat user";
         public const string NoKickOnCop  = "No, you won´t, you´ĺl never do kick a cop, it is the bad.";
-        public const string LabNoJoinNoSend = "LabnoJoinNoSend";
+        public const string LabNoJoinNoSend = "LabNoJoinNoSend";
     }
 }
diff --git a/src/Yavsc.Abstract/Constants.cs b/src/Yavsc.Abstract/Constants.cs
index a2649491c..ca871f9d5 100644
--- a/src/Yavsc.Abstract/Constants.cs
+++ b/src/Yavsc.Abstract/Constants.cs
@@ -13,6 +13,7 @@ namespace Yavsc
         public const string BlogTagPath = "blogtag";
         public const string CirclePath = "circle";
         public const string CommentsPath = "blogcomments";
+        public const string ChatHubPath = "chathub";
 
         public static readonly Scope[] SiteScopes = {
             new Scope { Id = "profile", Description = "Your profile informations" },
diff --git a/src/Yavsc.Api/Program.cs b/src/Yavsc.Api/Program.cs
index 8daff34d9..03c93e446 100644
--- a/src/Yavsc.Api/Program.cs
+++ b/src/Yavsc.Api/Program.cs
@@ -11,6 +11,7 @@ using Yavsc.Models;
 using Yavsc;
 using Yavsc.Server.Helpers;
 using Yavsc.Services;
+using Yavsc.Server.Hubs;
 
 internal class Program
 {
@@ -114,13 +115,11 @@ internal class Program
                 .UseRouting()
                 .UseAuthentication()
                 .UseAuthorization()
-                .UseCors("default")
-                ;
+                .UseCors("default");
             app.MapIdentityApi<ApplicationUser>().RequireAuthorization("ApiScope");
             app.MapDefaultControllerRoute();
-
-
             app.UseSession();
+            app.MapHub<ChatHub>("/" + Constants.ChatHubPath);
             await app.RunAsync();
         }
     }
diff --git a/src/Yavsc.Org/Controllers/Accounting/ManageController.cs b/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
index e09bbb5a4..32357c2c5 100644
--- a/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
+++ b/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
@@ -400,7 +400,7 @@ namespace Yavsc.Controllers
 
         public IActionResult SetUserName()
         {
-            return View(new SetUserNameViewModel() { UserName = User.Identity.Name });
+            return View(new SetUserNameViewModel() { UserName = User.GetUserName() });
         }
 
         [HttpPost]
diff --git a/src/Yavsc.Org/Extensions/HostingExtensions.cs b/src/Yavsc.Org/Extensions/HostingExtensions.cs
index cc593b860..563a74789 100644
--- a/src/Yavsc.Org/Extensions/HostingExtensions.cs
+++ b/src/Yavsc.Org/Extensions/HostingExtensions.cs
@@ -1053,8 +1053,6 @@ public static class HostingExtensions
         app.UseCors("default");
         app.MapDefaultControllerRoute();
         app.MapStaticAssets(staticAssetsManifestPath);
-        //app.MapRazorPages();
-        app.MapHub<ChatHub>("/chathub");
 
         WorkflowHelpers.ConfigureBillingService();
 
diff --git a/src/Yavsc.Server/Helpers/ServiceExtensions.cs b/src/Yavsc.Server/Helpers/ServiceExtensions.cs
index 397eada85..db5dbe983 100644
--- a/src/Yavsc.Server/Helpers/ServiceExtensions.cs
+++ b/src/Yavsc.Server/Helpers/ServiceExtensions.cs
@@ -128,7 +128,29 @@ public static class ServiceExtensions
             options.ClaimsIssuer = authority;
             options.Audience = audiences[0];
 
+            // Sending the access token in the query string is required when using WebSockets or ServerSentEvents
+            // due to a limitation in Browser APIs. We restrict it to only calls to the
+            // SignalR hub in this code.
+            // See https://docs.microsoft.com/aspnet/core/signalr/security#access-token-logging
+            // for more information about security considerations when using
+            // the query string to transmit the access token.
+            options.Events = new JwtBearerEvents
+            {
+                OnMessageReceived = context =>
+                {
+                    var accessToken = context.Request.Query["access_token"];
 
+                    // If the request is for our hub...
+                    var path = context.HttpContext.Request.Path;
+                    if (!string.IsNullOrEmpty(accessToken) &&
+                        (path.StartsWithSegments("/hubs/chat")))
+                    {
+                        // Read the token out of the query string
+                        context.Token = accessToken;
+                    }
+                    return Task.CompletedTask;
+                }
+            };
             // Dev: every Yavsc resource service (Yavsc.Api, Yavsc.Blogs,
             // Yavsc.Org itself) validates JWTs against the OP that runs
             // on https://localhost:5001 with a self-signed dev cert.
diff --git a/src/Yavsc.Server/Hubs/ChatHub.cs b/src/Yavsc.Server/Hubs/ChatHub.cs
index 799f7441c..61640b7e3 100644
--- a/src/Yavsc.Server/Hubs/ChatHub.cs
+++ b/src/Yavsc.Server/Hubs/ChatHub.cs
@@ -24,6 +24,7 @@
 using Microsoft.AspNetCore.SignalR;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Localization;
+
 #pragma warning disable CS4014 // Dans la mesure où cet appel n'est pas attendu, l'exécution de la méthode actuelle continue avant la fin de l'appel
 
 namespace Yavsc.Server.Hubs
@@ -36,6 +37,8 @@ namespace Yavsc.Server.Hubs
     using Yavsc.Models.Chat;
     using Yavsc.Server.Helpers;
     using Yavsc.Services;
+
+    [Authorize]
     public partial class ChatHub : Hub, IDisposable
     {
         private readonly ApplicationDbContext _dbContext;
@@ -53,100 +56,70 @@ namespace Yavsc.Server.Hubs
             _dbContext = dbContext;
             _localizer = stringLocalizerFactory.Create(typeof(ChatHub));
 
-            _cxManager =  connexionManager;
-            _cxManager.SetErrorHandler ((context, error) =>
+            _cxManager = connexionManager;
+            _cxManager.SetErrorHandler((context, error) =>
             {
                 NotifyUser(NotificationTypes.Error, context, error);
             });
             _logger = loggerFactory.CreateLogger<ChatHub>();
-            InputValidator = new HubInputValidator(_localizer) {
+            InputValidator = new HubInputValidator(_localizer)
+            {
 
-                NotifyUser = async (type, target, msg) => await this.NotifyUser(type, target, msg) };
-        }
-
-        void SetUserName(string cxId, string userName)
-        {
-            _cxManager.SetUserName(cxId,  userName);
+                NotifyUser = async (type, target, msg) => await this.NotifyUser(type, target, msg)
+            };
         }
 
         public override async Task OnConnectedAsync()
         {
-            bool isAuth = Context.User?.Identity?.IsAuthenticated ?? false;
+            var user = Context.User;
             bool isCop = false;
-            string userName = setUserName();
-            if (isAuth)
+            string userName = user.GetUserName();
+
+            _logger.LogInformation(_localizer.GetString(ChatHubConstants.LabAuthChatUser));
+
+            var userId = _dbContext.Users.First(u => u.UserName == userName).Id;
+
+            await Clients.Group(ChatHubConstants.HubGroupFollowingPrefix + userId).SendAsync("notifyUser", NotificationTypes.Connected, userName, null);
+            isCop = Context.User.IsInMsRole(Constants.AdminGroupName);
+            if (isCop)
             {
-
-                var group = isAuth ?
-                 ChatHubConstants.HubGroupAuthenticated : ChatHubConstants.HubGroupAnonymous;
-                // Log ("Cx: " + group);
-                await Groups.AddToGroupAsync(Context.ConnectionId, group);
-                _logger.LogInformation(_localizer.GetString(ChatHubConstants.LabAuthChatUser));
-
-                var userId = _dbContext.Users.First(u => u.UserName == Context.User.Identity.Name).Id;
-
-                await Clients.Group(ChatHubConstants.HubGroupFollowingPrefix + userId).SendAsync("notifyUser",  NotificationTypes.Connected, userName, null);
-                isCop = Context.User.IsInMsRole(Constants.AdminGroupName) ;
-                if (isCop)
-                {
-                    await Groups.AddToGroupAsync(Context.ConnectionId, ChatHubConstants.HubGroupCops);
-                }
-
-                foreach (var uid in _dbContext.CircleMembers.Select(m => m.MemberId))
-                {
-                    await Groups.AddToGroupAsync(Context.ConnectionId, ChatHubConstants.HubGroupFollowingPrefix + uid);
-                }
+                await Groups.AddToGroupAsync(Context.ConnectionId, ChatHubConstants.HubGroupCops);
             }
-            else
+
+            foreach (var uid in _dbContext.CircleMembers.Select(m => m.MemberId))
             {
-                await Groups.AddToGroupAsync(Context.ConnectionId, ChatHubConstants.HubGroupAnonymous);
+                await Groups.AddToGroupAsync(Context.ConnectionId, ChatHubConstants.HubGroupFollowingPrefix + uid);
             }
             _cxManager.OnConnected(Context.ConnectionId, isCop);
             await base.OnConnectedAsync();
         }
 
-        string setUserName(string queryUname = "anon")
-        {
-            if (Context.User != null)
-                if (Context.User.Identity.IsAuthenticated)
-                {
-                    SetUserName(Context.ConnectionId, Context.User.Identity.Name);
-                    return Context.User.Identity.Name;
-                }
-            anonymousSequence++;
-            var anonymousName = $"{ChatHubConstants.AnonymousUserNamePrefix}{queryUname}{anonymousSequence}";
-            SetUserName(Context.ConnectionId, anonymousName);
-            return anonymousName;
-        }
-
-        static long anonymousSequence = 0;
-
         public override async Task OnDisconnectedAsync(Exception ex)
         {
-            string userName = Context.User?.Identity.Name;
+            string userName = Context.User?.GetUserName();
             if (userName != null)
             {
                 var user = _dbContext.Users.FirstOrDefault(u => u.UserName == userName);
-                var userId = user.Id;
-                await Clients.Group(ChatHubConstants.HubGroupFollowingPrefix + userId).SendAsync("notifyUser", NotificationTypes.DisConnected, userName, null);
+                if (user != null)
+                {
+                    var userId = user.Id;
+                    await Clients.Group(ChatHubConstants.HubGroupFollowingPrefix + userId).SendAsync("notifyUser", NotificationTypes.DisConnected, userName, null);
+                }
 
                 _cxManager.OnDisconnected(Context.ConnectionId);
             }
-              await base.OnDisconnectedAsync(ex);
+            await base.OnDisconnectedAsync(ex);
         }
 
-
-        public async Task Nick(string nickName)
+        /// <summary>
+        /// Renvoie le login résolu côté serveur (claim <c>name</c> de
+        /// l'organisation Yavsc.Org, via <see cref="UserHelpers.GetUserName"/>).
+        /// Permet au client d'afficher l'identité réellement authentifiée,
+        /// sans jamais faire confiance à un pseudo fourni par le client.
+        /// </summary>
+        public string WhoAmI()
         {
-            if (!InputValidator.ValidateUserName(nickName)) return;
-
-            var candidate = "?" + nickName;
-            if (_cxManager.IsConnected(candidate))
-            {
-                await NotifyUser(NotificationTypes.ExistingUserName, nickName, "aborting");
-                return;
-            }
-            _cxManager.SetUserName( Context.ConnectionId,  candidate);
+            return Context.User?.GetUserName() ?? string.Empty;
         }
 
         bool IsPresent(string roomName, string userName)
@@ -159,11 +132,11 @@ namespace Yavsc.Server.Hubs
             _logger.LogInformation($"Join:{roomName}");
             if (!InputValidator.ValidateRoomName(roomName))
             {
-               _logger.LogError("!InputValidator.ValidateRoomName(roomName)");
+                _logger.LogError("!InputValidator.ValidateRoomName(roomName)");
                 return null;
             }
 
-            var roomGroupName = ChatHubConstants.HubGroupRomsPrefix + roomName;
+            var roomGroupName = ChatHubConstants.HubGroupRoomsPrefix + roomName;
             var user = _cxManager.GetUserName(Context.ConnectionId);
             await Groups.AddToGroupAsync(Context.ConnectionId, roomGroupName);
             ChatRoomInfo channelInfo;
@@ -172,7 +145,9 @@ namespace Yavsc.Server.Hubs
                 _logger.LogInformation($"Joining");
                 channelInfo = _cxManager.Join(roomName, Context.ConnectionId);
                 await Clients.Group(roomGroupName).SendAsync("notifyRoom", NotificationTypes.UserJoin, roomName, user);
-            } else {
+            }
+            else
+            {
                 _logger.LogInformation($"already present");
                 // in case in an additional connection,
                 // one only send info on room without
@@ -185,14 +160,13 @@ namespace Yavsc.Server.Hubs
             return channelInfo;
         }
 
-        [Authorize]
         public void Register(string room)
         {
-            if (!InputValidator.ValidateRoomName(room)) return ;
+            if (!InputValidator.ValidateRoomName(room)) return;
             var existent = _dbContext.ChatRoom.Any(r => r.Name == room);
             if (existent)
             {
-               NotifyUserInRoom(NotificationTypes.Error, room, "already registered.");
+                NotifyUserInRoom(NotificationTypes.Error, room, "already registered.");
                 return;
             }
             Debug.Assert(Context.User != null);
@@ -212,27 +186,25 @@ namespace Yavsc.Server.Hubs
             _dbContext.SaveChanges(user.Id);
         }
 
-        [Authorize]
-        public void KickBan(string roomName,  string userName, string reason)
+        public void KickBan(string roomName, string userName, string reason)
         {
-            if (!InputValidator.ValidateRoomName(roomName)) return ;
-            if (!InputValidator.ValidateUserName(userName)) return ;
+            if (!InputValidator.ValidateRoomName(roomName)) return;
+            if (!InputValidator.ValidateUserName(userName)) return;
             if (!InputValidator.ValidateReason(reason)) return;
             Kick(roomName, userName, reason);
             Ban(roomName, userName, reason);
         }
 
-        [Authorize]
-        public async Task Kick(string roomName,  string userName,  string reason)
+        public async Task Kick(string roomName, string userName, string reason)
         {
-            if (!InputValidator.ValidateRoomName(roomName)) return ;
-            if (!InputValidator.ValidateUserName(userName)) return ;
+            if (!InputValidator.ValidateRoomName(roomName)) return;
+            if (!InputValidator.ValidateUserName(userName)) return;
             if (!InputValidator.ValidateReason(reason)) return;
             ChatRoomInfo channelInfo;
-            var roomGroupName = ChatHubConstants.HubGroupRomsPrefix + roomName;
+            var roomGroupName = ChatHubConstants.HubGroupRoomsPrefix + roomName;
             if (_cxManager.TryGetChanInfo(roomName, out channelInfo))
             {
-                if (!_cxManager.IsPresent(roomName,userName))
+                if (!_cxManager.IsPresent(roomName, userName))
                 {
                     NotifyErrorToCallerInRoom(roomName, $"{userName} was not found in {roomName}.");
                     return;
@@ -242,44 +214,44 @@ namespace Yavsc.Server.Hubs
                 if (!_cxManager.Kick(Context.ConnectionId, userName, roomName, reason)) return;
             }
             var cxIds = _cxManager.GetConnexionIds(userName);
-            if (cxIds!=null) foreach(var cx in cxIds)
+            if (cxIds != null) foreach (var cx in cxIds)
                 await Groups.RemoveFromGroupAsync(cx, roomGroupName);
             await Clients.Group(roomGroupName).SendAsync("notifyRoom", NotificationTypes.Kick, roomName, $"{userName}: {reason}");
         }
 
-        [Authorize]
-        public void Ban(string roomName,  string userName,  string reason)
+        public void Ban(string roomName, string userName, string reason)
         {
-            if (!InputValidator.ValidateRoomName(roomName)) return ;
-            if (!InputValidator.ValidateUserName(userName)) return ;
+            if (!InputValidator.ValidateRoomName(roomName)) return;
+            if (!InputValidator.ValidateUserName(userName)) return;
             if (!InputValidator.ValidateReason(reason)) return;
             var cxIds = _cxManager.GetConnexionIds(userName);
             throw new NotImplementedException();
         }
 
-        [Authorize]
-        public void GLine(string userName,  string reason)
+        [Authorize(Constants.AdminGroupName)]
+        public void GLine(string userName, string reason)
         {
-            if (!InputValidator.ValidateUserName(userName)) return ;
+            if (!InputValidator.ValidateUserName(userName)) return;
             if (!InputValidator.ValidateReason(reason)) return;
             throw new NotImplementedException();
         }
 
-        public void Part(string roomName,  string reason)
+        public void Part(string roomName, string reason)
         {
-            if (!InputValidator.ValidateRoomName(roomName)) return ;
+            if (!InputValidator.ValidateRoomName(roomName)) return;
             if (!InputValidator.ValidateReason(reason)) return;
-            if (_cxManager.Part(Context.ConnectionId,  roomName,   reason))
-             {
-                var roomGroupName = ChatHubConstants.HubGroupRomsPrefix + roomName;
+            if (_cxManager.Part(Context.ConnectionId, roomName, reason))
+            {
+                var roomGroupName = ChatHubConstants.HubGroupRoomsPrefix + roomName;
                 var group = Clients.Group(roomGroupName);
                 var userName = _cxManager.GetUserName(Context.ConnectionId);
                 group.SendAsync("notifyRoom", NotificationTypes.UserPart, roomName, $"{userName}: {reason}");
                 Groups.RemoveFromGroupAsync(Context.ConnectionId, roomGroupName);
-             }
-             else {
-                 _logger.LogError("Could not part");
-             }
+            }
+            else
+            {
+                _logger.LogError("Could not part");
+            }
         }
 
         void NotifyErrorToCallerInRoom(string room, string reason)
@@ -288,19 +260,21 @@ namespace Yavsc.Server.Hubs
             _logger.LogError($"NotifyErrorToCallerInRoom: {room}, {reason}");
         }
 
-        public async Task Send(string roomName,  string message)
+        public async Task Send(string roomName, string message)
         {
             _logger.LogInformation($"Send {roomName} {message}");
-            if (!InputValidator.ValidateRoomName(roomName))  {
+            if (!InputValidator.ValidateRoomName(roomName))
+            {
                 _logger.LogError($"Invalid roomName : {roomName}");
-                return ;
+                return;
             }
-            if (!InputValidator.ValidateMessage(message))  {
+            if (!InputValidator.ValidateMessage(message))
+            {
                 _logger.LogError($"Invalid message : {message}");
-                return ;
+                return;
             }
-            var groupName = ChatHubConstants.HubGroupRomsPrefix + roomName;
-            ChatRoomInfo channelInfo ;
+            var groupName = ChatHubConstants.HubGroupRoomsPrefix + roomName;
+            ChatRoomInfo channelInfo;
             if (!_cxManager.TryGetChanInfo(roomName, out channelInfo))
             {
                 _logger.LogError($"No such room : {roomName}");
@@ -317,7 +291,7 @@ namespace Yavsc.Server.Hubs
                 return;
             }
             var group = Clients.Group(groupName);
-            var msg = new { Name = userName, Room = roomName, Message = message};
+            var msg = new { Name = userName, Room = roomName, Message = message };
             await group.SendAsync("ReceiveMessage", msg);
         }
 
@@ -332,8 +306,7 @@ namespace Yavsc.Server.Hubs
             await Clients.Caller.SendAsync("notifyUserInRoom", type, room, message);
         }
 
-        [Authorize]
-        public async Task SendPV(string userName,  string message)
+        public async Task SendPV(string userName, string message)
         {
             // Authorized code
             Debug.Assert(Context.User != null);
@@ -342,17 +315,17 @@ namespace Yavsc.Server.Hubs
             if (!InputValidator.ValidateUserName(userName))
             {
                 _logger.LogError($"Invalid username : {userName}");
-                return ;
+                return;
             }
             if (!InputValidator.ValidateMessage(message))
             {
                 _logger.LogError($"Invalid message : {message}");
-                return ;
+                return;
             }
             _logger.LogInformation($"Message form is validated.");
-                    var identityUserName = Context.User.GetUserName();
+            var identityUserName = Context.User.GetUserName();
 
-            if (userName[0] != '?' && Context.User!=null)
+            if (userName[0] != '?' && Context.User != null)
                 if (!Context.User.IsInMsRole(Constants.AdminGroupName))
                 {
 
@@ -373,7 +346,7 @@ namespace Yavsc.Server.Hubs
 
             _logger.LogInformation("getting cx id´s");
             var cxIds = _cxManager.GetConnexionIds(userName);
-            if (cxIds==null || cxIds.Count()==0)
+            if (cxIds == null || cxIds.Count() == 0)
                 _logger.LogError($"No such connected user : {userName}");
             else foreach (var connectionId in cxIds)
             {
@@ -385,18 +358,18 @@ namespace Yavsc.Server.Hubs
             }
         }
 
-        [Authorize]
-        public async Task SendStream(string connectionId, long streamId,  string message)
+        public async Task SendStream(string connectionId, long streamId, string message)
         {
             // Authorized code
             Debug.Assert(Context.User != null);
             Debug.Assert(Context.User.Identity != null);
             if (!InputValidator.ValidateMessage(message)) return;
-            var sender = Context.User.Identity.Name;
+            var sender = Context.User.GetUserName();
             var cli = Clients.Client(connectionId);
             await cli.SendAsync("addStreamInfo", sender, streamId, message);
         }
 
     }
 }
-#pragma warning restore CS4014 // Dans la mesure où cet appel n'est pas attendu, l'exécution de la méthode actuelle continue avant la fin de l'appel
+
+#pragma warning restore CS4014
diff --git a/src/Yavsc.Server/Interfaces/IConnexionManager.cs b/src/Yavsc.Server/Interfaces/IConnexionManager.cs
index 434054249..cf7c601e1 100644
--- a/src/Yavsc.Server/Interfaces/IConnexionManager.cs
+++ b/src/Yavsc.Server/Interfaces/IConnexionManager.cs
@@ -3,8 +3,6 @@ using Yavsc.ViewModels.Chat;
 namespace Yavsc.Services
 {
     public interface IConnexionManager {
-        void SetUserName(string cxId, string userName);
-
         string GetUserName (string cxId);
         void OnConnected(string cxId, bool isCop);
         bool IsConnected(string candidate);
diff --git a/src/Yavsc.Server/Services/HubConnectionManager.cs b/src/Yavsc.Server/Services/HubConnectionManager.cs
index 05ed49dda..e442151a1 100644
--- a/src/Yavsc.Server/Services/HubConnectionManager.cs
+++ b/src/Yavsc.Server/Services/HubConnectionManager.cs
@@ -53,23 +53,6 @@ namespace Yavsc.Services
             _localizer = stringLocFactory.Create(typeof(HubConnectionManager));
         }
 
-        public void SetUserName(string cxId, string userName)
-        {
-            string oldUname;
-            if (ChatUserNames.TryGetValue(cxId, out oldUname))
-            {
-                // this is a rename
-                if (oldUname == userName) return;
-                ChatCxIds[userName] = ChatCxIds[oldUname];
-                ChatCxIds[oldUname] = null;
-            }
-            else
-            {
-                // this is a connexion
-                ChatCxIds[userName] = new List<string>() { cxId };
-            }
-            ChatUserNames[cxId] = userName;
-        }
         // Username must have been set before calling this method.
         public void OnConnected(string cxId,  bool isCop)
         {