diff --git a/ViewModels/SocialSlotViewModel.cs b/ViewModels/SocialSlotViewModel.cs
new file mode 100644
index 0000000..2b7aecf
--- /dev/null
+++ b/ViewModels/SocialSlotViewModel.cs
@@ -0,0 +1,183 @@
+using System.ComponentModel;
+using ytLive.Helpers;
+using ytLive.Models;
+using ytLive.ViewModels;
+
+namespace ytLive.ViewModels;
+public sealed record DialogEntry(SocialService Service, string Handle, string ProfileUrl, string? FediverseSoftware = null);
+
+/// <summary>
+/// One of the six fixed dialog rows. Row 0 is always YouTube (signed-in account
+/// or a sign-in prompt); rows 1-5 hold validated entries, an empty slot, or — on
+/// the free tier — a locked "Premium" slot. Rows are a positional projection of
+/// the dialog's working list, so deleting an entry makes the ones above advance up.
+/// </summary>
+public sealed class SocialSlotViewModel : ViewModelBase
+{
+    public int Index { get; }
+    public bool IsYoutube => Index == 0;
+
+    private SocialService _service = SocialService.Link;
+    public SocialService Service
+    {
+        get => _service;
+        set { if (SetProperty(ref _service, value)) OnPropertyChanged(nameof(LogoData)); }
+    }
+
+    public string LogoData => Service == SocialService.Fediverse
+        ? SocialServiceIcons.LogoDataForFediverse(FediverseSoftware)
+        : SocialServiceIcons.LogoDataFor(Service);
+    public string LockedIconData => SocialServiceIcons.LockedIconData;
+    public string DoNotIconData => SocialServiceIcons.DoNotIconData;
+
+    private bool _isLocked;
+    public bool IsLocked
+    {
+        get => _isLocked;
+        set
+        {
+            if (SetProperty(ref _isLocked, value))
+            {
+                OnPropertyChanged(nameof(ShowAddButton));
+                OnPropertyChanged(nameof(ShowDoNot));
+                OnPropertyChanged(nameof(DisplayText));
+            }
+        }
+    }
+
+    private bool _isFilled;
+    public bool IsFilled
+    {
+        get => _isFilled;
+        set
+        {
+            if (SetProperty(ref _isFilled, value))
+            {
+                OnPropertyChanged(nameof(ShowEditButton));
+                OnPropertyChanged(nameof(ShowDeleteButton));
+                OnPropertyChanged(nameof(ShowAddButton));
+                OnPropertyChanged(nameof(ShowDoNot));
+                OnPropertyChanged(nameof(DisplayText));
+            }
+        }
+    }
+
+    private bool _isSignIn;
+    public bool IsSignIn
+    {
+        get => _isSignIn;
+        set
+        {
+            if (SetProperty(ref _isSignIn, value))
+            {
+                OnPropertyChanged(nameof(ShowSignInButton));
+                OnPropertyChanged(nameof(ShowDeleteButton));
+                OnPropertyChanged(nameof(ShowLogo));
+                OnPropertyChanged(nameof(DisplayText));
+            }
+        }
+    }
+
+    private bool _isEditing;
+    public bool IsEditing
+    {
+        get => _isEditing;
+        set
+        {
+            if (SetProperty(ref _isEditing, value))
+            {
+                OnPropertyChanged(nameof(ShowEditBox));
+                OnPropertyChanged(nameof(ShowDisplay));
+                OnPropertyChanged(nameof(ShowEditButton));
+                OnPropertyChanged(nameof(ShowDeleteButton));
+                OnPropertyChanged(nameof(ShowAddButton));
+                OnPropertyChanged(nameof(ShowDoNot));
+            }
+        }
+    }
+
+    private bool _isValidating;
+    public bool IsValidating
+    {
+        get => _isValidating;
+        set
+        {
+            if (SetProperty(ref _isValidating, value))
+            {
+                OnPropertyChanged(nameof(ShowBusy));
+                OnPropertyChanged(nameof(ShowDoNot));
+            }
+        }
+    }
+
+    private string _handle = string.Empty;
+    public string Handle
+    {
+        get => _handle;
+        set
+        {
+            if (SetProperty(ref _handle, value))
+                OnPropertyChanged(nameof(DisplayText));
+        }
+    }
+
+    private string? _fediverseSoftware;
+    public string? FediverseSoftware
+    {
+        get => _fediverseSoftware;
+        set
+        {
+            if (SetProperty(ref _fediverseSoftware, value))
+                OnPropertyChanged(nameof(LogoData));
+        }
+    }
+
+    public string ProfileUrl { get; set; } = string.Empty;
+
+    private string? _error;
+    public string? Error
+    {
+        get => _error;
+        set
+        {
+            if (SetProperty(ref _error, value))
+            {
+                OnPropertyChanged(nameof(HasError));
+                OnPropertyChanged(nameof(ShowError));
+                OnPropertyChanged(nameof(ShowDoNot));
+            }
+        }
+    }
+
+    private string _editText = string.Empty;
+    public string EditText
+    {
+        get => _editText;
+        set => SetProperty(ref _editText, value);
+    }
+
+    /// <summary>The last text submitted for validation (used to skip re-validating
+    /// identical input — e.g. a LostFocus firing as the user clicks Cancel).</summary>
+    public string? LastValidatedInput { get; set; }
+
+    public string DisplayText =>
+        IsYoutube
+            ? (IsSignIn ? "Sign in to YouTube" : Handle)
+            : IsLocked ? "Unlock with Premium"
+            : IsFilled ? Handle
+            : "No social yet";
+
+    public bool HasError => !string.IsNullOrEmpty(Error);
+    public bool ShowError => HasError;
+    public bool ShowLogo => IsYoutube ? !IsSignIn : IsFilled;
+    public bool ShowBusy => IsValidating;
+    public bool ShowEditBox => IsEditing;
+    public bool ShowDisplay => !IsEditing && !IsValidating;
+    public bool ShowSignInButton => IsYoutube && IsSignIn && !IsValidating;
+    public bool ShowAddButton => !IsYoutube && !IsLocked && !IsFilled && !IsEditing && !IsValidating;
+    public bool ShowEditButton => !IsYoutube && IsFilled && !IsEditing && !IsValidating;
+    public bool ShowDeleteButton => (IsFilled || IsYoutube) && !IsEditing && !IsValidating;
+    public bool ShowDoNot => !IsYoutube && !IsLocked && (!IsFilled || HasError || IsValidating);
+
+    public SocialSlotViewModel(int index) => Index = index;
+}
diff --git a/ViewModels/SocialsDialogViewModel.cs b/ViewModels/SocialsDialogViewModel.cs
index 08864f2..3903ec5 100644
--- a/ViewModels/SocialsDialogViewModel.cs
+++ b/ViewModels/SocialsDialogViewModel.cs
@@ -8,187 +8,6 @@ using ytLive.Services;
 
 namespace ytLive.ViewModels;
 
-/// <summary>
-/// A validated social entry in the dialog's working copy (non-YouTube slots).
-/// </summary>
-public sealed record DialogEntry(SocialService Service, string Handle, string ProfileUrl, string? FediverseSoftware = null);
-
-/// <summary>
-/// One of the six fixed dialog rows. Row 0 is always YouTube (signed-in account
-/// or a sign-in prompt); rows 1-5 hold validated entries, an empty slot, or — on
-/// the free tier — a locked "Premium" slot. Rows are a positional projection of
-/// the dialog's working list, so deleting an entry makes the ones above advance up.
-/// </summary>
-public sealed class SocialSlotViewModel : ViewModelBase
-{
-    public int Index { get; }
-    public bool IsYoutube => Index == 0;
-
-    private SocialService _service = SocialService.Link;
-    public SocialService Service
-    {
-        get => _service;
-        set { if (SetProperty(ref _service, value)) OnPropertyChanged(nameof(LogoData)); }
-    }
-
-    public string LogoData => Service == SocialService.Fediverse
-        ? SocialServiceIcons.LogoDataForFediverse(FediverseSoftware)
-        : SocialServiceIcons.LogoDataFor(Service);
-    public string LockedIconData => SocialServiceIcons.LockedIconData;
-    public string DoNotIconData => SocialServiceIcons.DoNotIconData;
-
-    private bool _isLocked;
-    public bool IsLocked
-    {
-        get => _isLocked;
-        set
-        {
-            if (SetProperty(ref _isLocked, value))
-            {
-                OnPropertyChanged(nameof(ShowAddButton));
-                OnPropertyChanged(nameof(ShowDoNot));
-                OnPropertyChanged(nameof(DisplayText));
-            }
-        }
-    }
-
-    private bool _isFilled;
-    public bool IsFilled
-    {
-        get => _isFilled;
-        set
-        {
-            if (SetProperty(ref _isFilled, value))
-            {
-                OnPropertyChanged(nameof(ShowEditButton));
-                OnPropertyChanged(nameof(ShowDeleteButton));
-                OnPropertyChanged(nameof(ShowAddButton));
-                OnPropertyChanged(nameof(ShowDoNot));
-                OnPropertyChanged(nameof(DisplayText));
-            }
-        }
-    }
-
-    private bool _isSignIn;
-    public bool IsSignIn
-    {
-        get => _isSignIn;
-        set
-        {
-            if (SetProperty(ref _isSignIn, value))
-            {
-                OnPropertyChanged(nameof(ShowSignInButton));
-                OnPropertyChanged(nameof(ShowDeleteButton));
-                OnPropertyChanged(nameof(ShowLogo));
-                OnPropertyChanged(nameof(DisplayText));
-            }
-        }
-    }
-
-    private bool _isEditing;
-    public bool IsEditing
-    {
-        get => _isEditing;
-        set
-        {
-            if (SetProperty(ref _isEditing, value))
-            {
-                OnPropertyChanged(nameof(ShowEditBox));
-                OnPropertyChanged(nameof(ShowDisplay));
-                OnPropertyChanged(nameof(ShowEditButton));
-                OnPropertyChanged(nameof(ShowDeleteButton));
-                OnPropertyChanged(nameof(ShowAddButton));
-                OnPropertyChanged(nameof(ShowDoNot));
-            }
-        }
-    }
-
-    private bool _isValidating;
-    public bool IsValidating
-    {
-        get => _isValidating;
-        set
-        {
-            if (SetProperty(ref _isValidating, value))
-            {
-                OnPropertyChanged(nameof(ShowBusy));
-                OnPropertyChanged(nameof(ShowDoNot));
-            }
-        }
-    }
-
-    private string _handle = string.Empty;
-    public string Handle
-    {
-        get => _handle;
-        set
-        {
-            if (SetProperty(ref _handle, value))
-                OnPropertyChanged(nameof(DisplayText));
-        }
-    }
-
-    private string? _fediverseSoftware;
-    public string? FediverseSoftware
-    {
-        get => _fediverseSoftware;
-        set
-        {
-            if (SetProperty(ref _fediverseSoftware, value))
-                OnPropertyChanged(nameof(LogoData));
-        }
-    }
-
-    public string ProfileUrl { get; set; } = string.Empty;
-
-    private string? _error;
-    public string? Error
-    {
-        get => _error;
-        set
-        {
-            if (SetProperty(ref _error, value))
-            {
-                OnPropertyChanged(nameof(HasError));
-                OnPropertyChanged(nameof(ShowError));
-                OnPropertyChanged(nameof(ShowDoNot));
-            }
-        }
-    }
-
-    private string _editText = string.Empty;
-    public string EditText
-    {
-        get => _editText;
-        set => SetProperty(ref _editText, value);
-    }
-
-    /// <summary>The last text submitted for validation (used to skip re-validating
-    /// identical input — e.g. a LostFocus firing as the user clicks Cancel).</summary>
-    public string? LastValidatedInput { get; set; }
-
-    public string DisplayText =>
-        IsYoutube
-            ? (IsSignIn ? "Sign in to YouTube" : Handle)
-            : IsLocked ? "Unlock with Premium"
-            : IsFilled ? Handle
-            : "No social yet";
-
-    public bool HasError => !string.IsNullOrEmpty(Error);
-    public bool ShowError => HasError;
-    public bool ShowLogo => IsYoutube ? !IsSignIn : IsFilled;
-    public bool ShowBusy => IsValidating;
-    public bool ShowEditBox => IsEditing;
-    public bool ShowDisplay => !IsEditing && !IsValidating;
-    public bool ShowSignInButton => IsYoutube && IsSignIn && !IsValidating;
-    public bool ShowAddButton => !IsYoutube && !IsLocked && !IsFilled && !IsEditing && !IsValidating;
-    public bool ShowEditButton => !IsYoutube && IsFilled && !IsEditing && !IsValidating;
-    public bool ShowDeleteButton => (IsFilled || IsYoutube) && !IsEditing && !IsValidating;
-    public bool ShowDoNot => !IsYoutube && !IsLocked && (!IsFilled || HasError || IsValidating);
-
-    public SocialSlotViewModel(int index) => Index = index;
-}
-
 /// <summary>
 /// View model for the Social Media Site Promotion dialog. Owns the working copy
 /// of the social bar config: the six fixed slots, the sign-in gate, per-row
diff --git a/ViewModels/index.md b/ViewModels/index.md
index 4c69042..cce9911 100644
--- a/ViewModels/index.md
+++ b/ViewModels/index.md
@@ -69,5 +69,6 @@ commit, tag `refactor-commit-N`, no per-commit push).
 - [x] **Commit A · `refactor-commit-A`** — **core** → `MainViewModel.cs` 758 → **495**. Moved source add/remove/image block to new **`MainViewModel.Sources.cs`** (234 lines: `AddSource`, `NextSourceName`, `AddImage`, `BuildImageCandidates`, `PickImageBytes`, `AddAsset`, `AddImageSource`, `AddReusedImage`, `RemoveElement`) and WebView2 hosting (`RegisterLoadedWebSources`, `InitWebView2`, `OnWebView2PreviewBitmapChanged`) to new **`MainViewModel.Web.cs`**. Pruned now-dead usings (`Microsoft.Win32`, `NAudio.CoreAudioApi`, `System.Windows.Media.Imaging`, `Collections.ObjectModel/Specialized`). Pending: Streaming, Background, SocialsDialogViewModel, LayoutStore.
 - [x] **Commit B · `refactor-commit-B`** — **Streaming** → `MainViewModel.Streaming.cs` 789 → **330** + new **`MainViewModel.Streaming.Operations.cs`** (459 lines). Moved the go-live/record/health operation bodies (`StartSession`, `BeginRecordOnly`, `BeginGoLive`, `StartRecordFile`, `PrepareAndStartLiveAsync`, `PollHealthAsync`/`OnHealthPollTick`/`ApplyHealthIssue`, `StopStream`, `FinalizeRecordingAsync`, `UniquePath`, `ChooseRecordFolder`, `ResetRecordFolder`, `DefaultRecordFolder`, `OnFramePumpFailed`, `OnFramePumpHealthUpdated`, `ApplyHealth`, `ResetHealth`, `BuildEncoderOptions`) into the Operations partial; Streaming.cs keeps state + quality/resolution tiers + session timer + command declarations. Pruned dead usings both files. Pending: Background, SocialsDialogViewModel, LayoutStore.
 - [x] **Commit C · `refactor-commit-C`** — **Background** → `MainViewModel.Background.cs` 567 → **418** + new **`MainViewModel.Background.Model.cs`** (163 lines). Moved the static scene-model helpers (`LoadBackgroundImage`, `CreatePlaceholderSnapshot`, `EnsureBackground`, `CreateBackground`, `NormalizeBackgrounds`, `AllBackgrounds`, `ResolveAutoCaptureKey`, `MonitorKeyPrefix`) into the Model partial; Background.cs keeps capture/live state + operations (`UpdateActiveBackground`, `UpdateBackgroundImage`, `RefreshSnapshotsAsync`, `ReacquireScreenCaptures`, `OnScreenPreviewBitmapChanged`, `OnFullscreenMonitorChanged`, `RefreshBackgroundAutoCapture`, `BrowseBackground`, `ClearBackgroundCaptureAsync`, `RedesignateBackgroundAsync`, `ChangeBackgroundCaptureAsync`, `SetBackgroundCapture`, `DefaultBackgroundAsset`, `HealBackgrounds`, `StampDefaultBackgroundAsset`). Pending: SocialsDialogViewModel, LayoutStore.
+- [x] **Commit D · `refactor-commit-D`** — **SocialsDialog** → `SocialsDialogViewModel.cs` 515 → **334** + new **`SocialSlotViewModel.cs`** (183 lines). Moved the `DialogEntry` record + the row-level `SocialSlotViewModel` (six-fixed-slot row VM: service/logo/lock/edit/validate state + computed `Show*` flags) into its own file; `SocialsDialogViewModel.cs` keeps the dialog VM (sign-in gate, validation orchestration, commit). `DialogEntry` stays `public` in the same namespace so both files see it. Pending: LayoutStore.
 The partial `.cs` files land next to `MainViewModel.cs` in this folder as the split
 proceeds; each partial carries its own `using`s and re-declares nothing from core.
\ No newline at end of file