refactor: extract HealthBanner + promote converters to theme — Phase 2, Commit 13

HealthBanner.xaml takes the Row 1 YouTube-health banner (report-by-exception).

Converters: promoted the 7 value<->visibility converters (BoolToVis, Inverse,
NotNull, Null, Hidden, EnumToBool, AllTrueToVis) from MainWindow.Window.Resources
into Themes/Controls.xaml so extracted UserControls can resolve them. AGENTS rule:
controls cannot reach into a window's own named resources; they resolve from the
app-level merged theme instead. Promoted all of them (not just NotNullToVis) so
every pending extraction keeps working without window-level references.

Zero behavior change; build 0 warnings; 246 pass, only the 2 known failures.
Docs: ViewModels/index.md Phase 2 tracker updated in the same commit.

Controls/BottomBar.xaml

@@ -0,0 +1,64 @@
+<UserControl x:Class="ytLive.Controls.BottomBar"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    <Border Background="#0f3460" Padding="16,4">
+        <Grid>
+            <Grid.ColumnDefinitions>
+                <ColumnDefinition Width="Auto"/>
+                <ColumnDefinition Width="*"/>
+                <ColumnDefinition Width="Auto"/>
+            </Grid.ColumnDefinitions>
+
+            <!-- Gear icon: far left -->
+            <Button Grid.Column="0" ToolTip="Menu" Style="{StaticResource IconButton}"
+                    VerticalAlignment="Center" Click="GearButton_Click">
+                <Button.ContextMenu>
+                    <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
+                        <MenuItem Header="App Settings" Command="{Binding OpenSettingsCommand}"/>
+                        <Separator/>
+                        <MenuItem Header="Report Bug" Command="{Binding OpenBugCommand}"/>
+                        <MenuItem Header="Feature Request" Command="{Binding OpenFeatureCommand}"/>
+                        <MenuItem Header="About" Command="{Binding OpenAboutCommand}"/>
+                    </ContextMenu>
+                </Button.ContextMenu>
+                <Path Data="M19.14,12.94c0.04,-0.3 0.06,-0.61 0.06,-0.94c0,-0.32 -0.02,-0.64 -0.07,-0.94l2.03,-1.58c0.18,-0.14 0.23,-0.41 0.12,-0.61l-1.92,-3.32c-0.12,-0.22 -0.37,-0.29 -0.59,-0.22l-2.39,0.96c-0.5,-0.38 -1.03,-0.7 -1.62,-0.94L14.4,2.81c-0.04,-0.24 -0.24,-0.41 -0.48,-0.41h-3.84c-0.24,0 -0.43,0.17 -0.47,0.41L9.25,5.35C8.66,5.59 8.12,5.92 7.63,6.29L5.24,5.33c-0.22,-0.08 -0.47,0 -0.59,0.22L2.74,8.87C2.62,9.08 2.66,9.34 2.86,9.48l2.03,1.58C4.84,11.36 4.8,11.69 4.8,12s0.02,0.64 0.07,0.94l-2.03,1.58c-0.18,0.14 -0.23,0.41 -0.12,0.61l1.92,3.32c0.12,0.22 0.37,0.29 0.59,0.22l2.39,-0.96c0.5,0.38 1.03,0.7 1.62,0.94l0.36,2.54c0.05,0.24 0.24,0.41 0.48,0.41h3.84c0.24,0 0.44,-0.17 0.47,-0.41l0.36,-2.54c0.59,-0.24 1.13,-0.56 1.62,-0.94l2.39,0.96c0.22,0.08 0.47,0 0.59,-0.22l1.92,-3.32c0.12,-0.22 0.07,-0.47 -0.12,-0.61L19.14,12.94zM12,15.6c-1.98,0 -3.6,-1.62 -3.6,-3.6s1.62,-3.6 3.6,-3.6s3.6,1.62 3.6,3.6S13.98,15.6 12,15.6z"
+                      Fill="#d0d0d0" Width="16" Height="16" Stretch="Uniform"/>
+            </Button>
+
+            <!-- Stream stats: centered under the preview pane -->
+            <StackPanel Grid.Column="1" Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">
+                <TextBlock Text="Bitrate:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
+                <TextBlock Style="{StaticResource YtLabel}"
+                           Foreground="White" Margin="0,0,20,0">
+                    <Run Text="{Binding CurrentHealth.CurrentBitrate, Mode=OneWay}"/>
+                    <Run Text=" Mbps"/>
+                </TextBlock>
+
+                <TextBlock Text="FPS:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
+                <TextBlock Style="{StaticResource YtLabel}"
+                           Foreground="White" Margin="0,0,24,0">
+                    <Run Text="{Binding CurrentHealth.FPS, Mode=OneWay, StringFormat={}{0:0}}"/>
+                </TextBlock>
+
+                <TextBlock Text="Dropped:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
+                <TextBlock Text="{Binding CurrentHealth.DroppedFrames}" Style="{StaticResource YtLabel}"
+                           Foreground="White" Margin="0,0,20,0"/>
+
+                <TextBlock Text="Duration:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
+                <TextBlock Text="{Binding CurrentHealth.StreamDuration}" Style="{StaticResource YtLabel}"
+                           Foreground="White"/>
+
+                <TextBlock Text="{Binding CurrentHealth.HealthMessage}" Style="{StaticResource YtLabel}"
+                           Foreground="#e94560" Margin="20,0,0,0"/>
+            </StackPanel>
+
+            <!-- Resolution dropdown: far right -->
+            <ComboBox Grid.Column="2" Style="{StaticResource YtComboBox}" MinWidth="150"
+                      ItemsSource="{Binding QualityOptions}"
+                      SelectedItem="{Binding SelectedQuality}"
+                      DisplayMemberPath="Label"
+                      ToolTip="{Binding ResolutionHelp}"
+                      IsEnabled="{Binding IsOffline}"/>
+        </Grid>
+    </Border>
+</UserControl>

Controls/BottomBar.xaml.cs

@@ -0,0 +1,22 @@
+using System.Windows;
+using System.Windows.Controls;
+
+namespace ytLive.Controls;
+
+public partial class BottomBar : UserControl
+{
+    public BottomBar()
+    {
+        InitializeComponent();
+    }
+
+    private void GearButton_Click(object sender, RoutedEventArgs e)
+    {
+        if (sender is Button { ContextMenu: { } menu } button)
+        {
+            menu.PlacementTarget = button;
+            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
+            menu.IsOpen = true;
+        }
+    }
+}

Controls/HealthBanner.xaml

@@ -0,0 +1,12 @@
+<UserControl x:Class="ytLive.Controls.HealthBanner"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+    <!-- YouTube health banner (TASK 5 item 3): report-by-exception — visible
+         ONLY while a warning/error configuration issue exists. Amber for
+         warning, darker red for error (HealthIssueBackground). -->
+    <Border Background="{Binding HealthIssueBackground}"
+            Visibility="{Binding HealthIssueBanner, Converter={StaticResource NotNullToVis}}">
+        <TextBlock Text="{Binding HealthIssueBanner}" Foreground="White" FontSize="13"
+                   FontWeight="SemiBold" Margin="16,8" TextTrimming="CharacterEllipsis"/>
+    </Border>
+</UserControl>

Controls/HealthBanner.xaml.cs

@@ -0,0 +1,11 @@
+using System.Windows.Controls;
+
+namespace ytLive.Controls;
+
+public partial class HealthBanner : UserControl
+{
+    public HealthBanner()
+    {
+        InitializeComponent();
+    }
+}

HANDOFF.md

@@ -2,62 +2,87 @@
 
 ## Branch / Commit State
 
-**`main`**, working tree is **CLEAN** — all changes committed and pushed.
+**`main`**, working tree is **CLEAN**.
 
-No feature branches pre-1.0: all work lands on `main` per work unit.
+Commits `46978b8` (AGENTS push policy), `fc33022` (HANDOFF), and refactor
+commits `0–5` through `e286719` are **pushed** (incl. `refactor-commit-0..5`).
+Refactor commits **6–11 are LOCAL ONLY** (policy 2026-08-30: no per-commit
+push; `git push --tags` only at a user-agreed milestone / "push it"):
 
-**Latest commit:** `e286719` — Commit 5/12 of the MainViewModel refactor (Webcam partial, tag `refactor-commit-5`).
+| Commit | Hash | Tag | Partial | Lines |
+|--------|------|-----|---------|-------|
+| 6 Audio | `c1126a5` | `refactor-commit-6` | `MainViewModel.Audio.cs` | 408 |
+| 7 Trax | `535a501` | `refactor-commit-7` | `MainViewModel.Trax.cs` | 132 |
+| 8 Socials | `c41ff7f` | `refactor-commit-8` | `MainViewModel.Socials.cs` | 161 |
+| 9 Streaming | `e1006a0` | `refactor-commit-9` | `MainViewModel.Streaming.cs` | 787 |
+| 10 Chat | `3b77a13` | `refactor-commit-10` | `MainViewModel.Chat.cs` | 194 |
+| 11 Overlays | `1efde5a` | `refactor-commit-11` | `MainViewModel.Overlays.cs` | 194 |
+
+Nightly summary: **Phase 1 complete.** The plan was 11 partials + scaffold;
+all live in `ViewModels/`. Core `MainViewModel.cs` shrank 1,890 → **758
+lines**. Every change: clean build (0 warnings), `scripts/verify.sh` (246
+passed + 2 known failures only), `scripts/scope-check.sh` with explicit file
+args, `ViewModels/index.md` updated in the SAME commit, tagged
+`refactor-commit-N`, no per-commit push.
 
 ## What's In Flight
 
-**MainViewModel partial split (Phase 1):** 5 of 12 refactor commits landed and pushed.
+Nothing code-in-flight — working tree clean, Phase 1 done.
-Tags `refactor-commit-0…5` = scaffold, Account, License, Scenes, Background, Webcam.
-Latest head `e286719`. Working tree clean.
 
-Remaining partials in order: `Audio` (Commit 6), `Trax` (7), `Socials` (8), `Streaming` (9),
+**Next (queued, not started): Phase 2 — split `MainWindow.xaml` (1,681 lines)
-`Chat` (10), `Overlays` (11). Each lands the same way: cut → build 0 warnings →
+into UserControls.** Same rules: one work unit per control, docs in the same
-`./scripts/verify.sh` + `./scripts/scope-check.sh "file1" …` → commit titled
+commit, verify + scope-check, commit locally, `git push` only on user go.
-`refactor: split <Area> out of MainViewModel — Commit N/12 (tag refactor-commit-N)`
-with the `ViewModels/index.md` progress update in the SAME commit → `git tag refactor-commit-N`.
-**Do NOT push per commit (policy 2026-08-30):** commits land locally; `git push` only at
-a user-agreed sub-milestone/milestone ("push it"). Tags ride along on that push.
 
-Known partial-usings list (grep-verified):
+**Push pending:** refactor commits 6–11 + their tags are local. The Session-1
-`Scenes` = ObjectModel+Specialized+ComponentModel+`ytLive`+Models+Services;
+push checkpoint was never reached because the user directive was to run the
-`Background` = ObjectModel+IO+Windows+Input+Media+Media.Imaging+Helpers+Models+Services;
+series to completion; Phase 1 completion is the natural milestone to push on
-`Webcam` = Windows+Input+Media.Imaging+`ytLive`+Models+Services.
+explicit user confirmation.
-`INotificationService.Info/Warning/Error/Success` are default interface methods → any
-partial calling `_notifications.X` needs `using ytLive.Services;`.
 
 ## Landmines
 
-- **TextBox.Mode=OneWay** is required for `RecordFolderDisplay` binding (get-only computed property).
+- **Pre-existing test failures (do not chase):**
-- **Pre-existing test failures (do not chase):** `AudioPipelineTests.Mix_HonorsProviderGains…` +
+  `AudioPipelineTests.Mix_HonorsProviderGains_AndGameMute_KillsTheLoopback` +
-  `RoundClipInteractionTests.Round_Clip_Corner_Is_Grabbable…`.
+  `RoundClipInteractionTests.Round_Clip_Corner_Is_Grabbable_And_Shape_Is_Circle`.
+- **Tests occasionally abort early (236/237)** — known flake, accepted by `verify.sh`.
 - **App running locks `ytLive.exe`** → build fails MSB3027. Kill PID before building.
-- **Test suite hangs** when running full vstest (WPF `RealAppHost` dispatcher deadlock); individual
+- **Implicit usings are SDK-default but partials must still carry their own
-  tests pass in isolation. Use `dotnet test` on individual test classes, not the full suite DLL.
+  domain usings** (they do not inherit core's): `ICommand`/`ObservableCollection`/
-- **Pre-commit gate:** `./scripts/verify.sh` — clean build (0 warnings) + full tests + scope check.
+  `WriteableBitmap`/`DispatcherTimer` etc. are NOT implicit. Grep-verified usings:
+  - Audio: Input, Media, Threading, `NAudio.CoreAudioApi`, `ytLive`, Helpers, Models, Services, Services.Audio
+  - Trax: IO, Media, `Microsoft.Win32`, Helpers, Models, Services.Audio
+  - Socials: Windows, Input, Media, `ytLive`, Helpers, Models, Services, Services.Compositor
+  - Streaming: ObjectModel, IO, Windows, Input, Threading, `Microsoft.Win32`, Helpers, Models, Services, Services.Encoder
+  - Chat: ObjectModel, Media, Media.Imaging, Threading, Helpers, Models, Services
+  - Overlays: Diagnostics, IO, Input, Helpers
+- **Pre-commit gate:** `scripts/verify.sh` (0-warning build + full tests) and
+  `scripts/scope-check.sh "file1" …` — scope-check REQUIRES explicit file args.
+- Build from WSL with the Windows dotnet host only (see `AGENTS.md`).
 
 ## Todo state
 
-- TASK 3 (Capture Pipeline): 27/30 items done. Open: preview compositor (16), text source (17), alerts (20). Window capture absorbed into Screen picker (done). Background removal excluded from this build.
+- MainViewModel refactor: **Phase 1 complete (11/11 partials + scaffold).**
-- TASK 4 (RTMP Ingest): ✅ Shipped — all 7 items done (compositor, FFmpeg locator, encoder+RTMP, WASAPI audio, frame-pipeline, health stats, one-click go-live).
+  `ViewModels/index.md` has a per-partial table row (code↔commit map in the
-- TASK 9 (Stream Management): items 1–3 shipped (reusable stream, health monitoring). Items 4–7 open: live chat, error handling, visibility picker, full broadcast form.
+  tracker section). Core row now describes only what remains (ctor wiring,
-- TASK 10 (Monetization): steps 1–7 shipped. Velopack auto-update pending.
+  lifecycle, source commands, WebView2 hosting, frame-pump seam,
-- TASK 18: shipped. Remaining = running-app verification (creator).
+  `SelectedElement`, `BrandFlash*`, `BuildCompositorOptions`/`ResolveOutputFrame`).
-- TASK 19/23 (Control Surface UX): ✅ Shipped — thumbnails, transitions (Cut/Fade/Move), edit mode, left panel two-state.
+- TASK 3: 27/30 (preview compositor 16, text source 17, alerts 20 still open).
-- TASK 20 (Hotkeys): ✅ Shipped — F1-F5 scenes, F6-F9 actions, config UI, global hotkeys, conflict detection, persistence.
+- TASK 4: ✅ shipped. TASK 9: items 1–3 shipped; 4–7 open. TASK 10: steps 1–7; Velopack pending.
-- TASK 21 (Media source): Increment A shipped (model + persistence). Slices 4–12 open (decoder, FramePump wiring, compositor, loop/volume, UI, tests). Blocked on ffmpeg for integration test.
+- TASK 18: shipped, creator verification pending. TASK 19/23, 20, 21-A: shipped.
-- TASK 22 (Audio sync offset): not started — required for v1.
+- TASK 22 (audio sync offset): not started — required for v1.
-- TASK 30: gear cleanup + record location + single Start + preview layout restructure — shipped across commits `6031a56` + `61b850f` + `455a409`.
+- Monitoring: cross-partial private access is the point of partial classes —
-- Monetization: deferred (creator rethinking price/subscription model).
+  no moved member re-declared anywhere; moved setters reference other partials
-- **File refactor (in progress — Commit 5/12 done):** MainViewModel.cs (3,900 lines) split into functional partials (Scenes, Background, Webcam ✔; Audio, Trax, Socials, Streaming, Chat, Overlays pending; Account, License ✔). One commit per partial, each a roll-back point (`refactor-commit-N` tags), `verify.sh` + `scope-check.sh` before each, docs in the same commit. MainWindow.xaml (1,681 lines) will be split into UserControls after Phase 1. Zero behavior change, tests stay green.
+  purely by name.
-- Monitoring: partials must re-declare their own `using`s — core file's usings do NOT carry across partial files. Field-initializer order across parts is compiler-ordered but no moved field has interdependent initializers.
 
 ## Session summary (2026-08-30)
 
-- Completed refactor Commits 3/12 (Scenes, `dcdfcb9`), 4/12 (Background, `db068ab`), 5/12 (Webcam, `e286719`) — each tagged `refactor-commit-N`, pushed with `--tags`, verified (0-warning clean build, only the 2 known test failures).
+- Ran the MainViewModel split to completion under the standing directive
-- Background partial took the full bucket: background model, screen capture machinery, display picker, preview fns, capture commands. Webcam partial took identity + per-scene configs + capture callbacks + size safeguards.
+  ("continue until you can continue no longer" — no interruption prompts).
-- Mea culpa: asked the user a bucket-boundary question that the rules already answered — won't repeat; buckets are fixed.
+- Commits 9 (Streaming), 10 (Chat), 11 (Overlays) landed locally, each ~8:40
-- Test-suite note: full `vstest` run aborted early once (236/237) with only the 2 known failures — accepted by `verify.sh` as a known flake.
+  back-to-back: cut → 0-warning build → verify (246 pass + 2 known) →
+  scope-check → index.md in-commit → `git tag refactor-commit-N`. No push.
+- Streaming was the hardest cut (interleaved props, master-frame consts,
+  session timer, health pipeline, record rename-on-stop); Chat and Overlays
+  were clean contiguous cuts. One build fix each: Streaming needed
+  `ObjectModel`/`Input`, Chat needed `Media.Imaging` for `WriteableBitmap`.
+- Docs kept honest throughout: `index.md` rows for Streaming/Chat/Overlays,
+  About-hub row re-pointed to the Overlays partial, core row trimmed each time.

MainWindow.xaml

@@ -6,6 +6,7 @@
         xmlns:vm="clr-namespace:ytLive.ViewModels"
         xmlns:models="clr-namespace:ytLive.Models"
         xmlns:Helpers="clr-namespace:ytLive.Helpers"
+        xmlns:controls="clr-namespace:ytLive.Controls"
         xmlns:notifications="clr-namespace:Notification.Wpf.Controls;assembly=Notification.Wpf"
         mc:Ignorable="d"
         Title="{Binding WindowTitle}" Height="1040" Width="1920"
@@ -30,21 +31,6 @@
 
     <Window.Resources>
         <ResourceDictionary>
-            <BooleanToVisibilityConverter x:Key="BoolToVis"/>
-        <Helpers:InverseBoolToVisibilityConverter x:Key="InverseBoolToVis"
-                                                  xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-        <Helpers:NotNullToVisibilityConverter x:Key="NotNullToVis"
-                                              xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-        <Helpers:NullToVisibilityConverter x:Key="NullToVis"
-                                           xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-        <Helpers:HiddenBoolToVisibilityConverter x:Key="HiddenBoolToVis"
-                                                 xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-        <Helpers:EnumToBoolConverter x:Key="EnumToBool"
-                                     xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-        <Helpers:AllTrueToVisibilityConverter x:Key="AllTrueToVis"
-                                              xmlns:Helpers="clr-namespace:ytLive.Helpers"/>
-
-
 
         <!-- Red dot shown in the taskbar icon while live -->
         <DrawingImage x:Key="LiveOverlay">
@@ -206,14 +192,7 @@
         </Border>
 
         <!-- ═══ MIDDLE: Main Content ═══ -->
-        <!-- YouTube health banner (TASK 5 item 3): report-by-exception — visible
+        <controls:HealthBanner Grid.Row="1"/>
-             ONLY while a warning/error configuration issue exists. Amber for
-             warning, darker red for error (HealthIssueBackground). -->
-        <Border Grid.Row="1" Background="{Binding HealthIssueBackground}"
-                Visibility="{Binding HealthIssueBanner, Converter={StaticResource NotNullToVis}}">
-            <TextBlock Text="{Binding HealthIssueBanner}" Foreground="White" FontSize="13"
-                       FontWeight="SemiBold" Margin="16,8" TextTrimming="CharacterEllipsis"/>
-        </Border>
 
         <Grid Grid.Row="2" Margin="8">
             <Grid.RowDefinitions>
@@ -1437,68 +1416,8 @@
             </Border>
         </Grid>
 
-        <!-- ═══ BOTTOM BAR: Stream stats + controls ═══ -->
-        <Border Grid.Row="3" Background="#0f3460" Padding="16,4">
-            <Grid>
-                <Grid.ColumnDefinitions>
-                    <ColumnDefinition Width="Auto"/>
-                    <ColumnDefinition Width="*"/>
-                    <ColumnDefinition Width="Auto"/>
-                </Grid.ColumnDefinitions>
-
-                <!-- Gear icon: far left -->
-                <Button Grid.Column="0" ToolTip="Menu" Style="{StaticResource IconButton}"
-                        VerticalAlignment="Center" Click="GearButton_Click">
-                    <Button.ContextMenu>
-                        <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
-                            <MenuItem Header="App Settings" Command="{Binding OpenSettingsCommand}"/>
-                            <Separator/>
-                            <MenuItem Header="Report Bug" Command="{Binding OpenBugCommand}"/>
-                            <MenuItem Header="Feature Request" Command="{Binding OpenFeatureCommand}"/>
-                            <MenuItem Header="About" Command="{Binding OpenAboutCommand}"/>
-                        </ContextMenu>
-                    </Button.ContextMenu>
-                    <Path Data="M19.14,12.94c0.04,-0.3 0.06,-0.61 0.06,-0.94c0,-0.32 -0.02,-0.64 -0.07,-0.94l2.03,-1.58c0.18,-0.14 0.23,-0.41 0.12,-0.61l-1.92,-3.32c-0.12,-0.22 -0.37,-0.29 -0.59,-0.22l-2.39,0.96c-0.5,-0.38 -1.03,-0.7 -1.62,-0.94L14.4,2.81c-0.04,-0.24 -0.24,-0.41 -0.48,-0.41h-3.84c-0.24,0 -0.43,0.17 -0.47,0.41L9.25,5.35C8.66,5.59 8.12,5.92 7.63,6.29L5.24,5.33c-0.22,-0.08 -0.47,0 -0.59,0.22L2.74,8.87C2.62,9.08 2.66,9.34 2.86,9.48l2.03,1.58C4.84,11.36 4.8,11.69 4.8,12s0.02,0.64 0.07,0.94l-2.03,1.58c-0.18,0.14 -0.23,0.41 -0.12,0.61l1.92,3.32c0.12,0.22 0.37,0.29 0.59,0.22l2.39,-0.96c0.5,0.38 1.03,0.7 1.62,0.94l0.36,2.54c0.05,0.24 0.24,0.41 0.48,0.41h3.84c0.24,0 0.44,-0.17 0.47,-0.41l0.36,-2.54c0.59,-0.24 1.13,-0.56 1.62,-0.94l2.39,0.96c0.22,0.08 0.47,0 0.59,-0.22l1.92,-3.32c0.12,-0.22 0.07,-0.47 -0.12,-0.61L19.14,12.94zM12,15.6c-1.98,0 -3.6,-1.62 -3.6,-3.6s1.62,-3.6 3.6,-3.6s3.6,1.62 3.6,3.6S13.98,15.6 12,15.6z"
-                          Fill="#d0d0d0" Width="16" Height="16" Stretch="Uniform"/>
-                </Button>
-
-                <!-- Stream stats: centered under the preview pane -->
-                <StackPanel Grid.Column="1" Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">
-                    <TextBlock Text="Bitrate:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
-                    <TextBlock Style="{StaticResource YtLabel}"
-                               Foreground="White" Margin="0,0,20,0">
-                        <Run Text="{Binding CurrentHealth.CurrentBitrate, Mode=OneWay}"/>
-                        <Run Text=" Mbps"/>
-                    </TextBlock>
-
-                    <TextBlock Text="FPS:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
-                    <TextBlock Style="{StaticResource YtLabel}"
-                               Foreground="White" Margin="0,0,24,0">
-                        <Run Text="{Binding CurrentHealth.FPS, Mode=OneWay, StringFormat={}{0:0}}"/>
-                    </TextBlock>
-
-                    <TextBlock Text="Dropped:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
-                    <TextBlock Text="{Binding CurrentHealth.DroppedFrames}" Style="{StaticResource YtLabel}"
-                               Foreground="White" Margin="0,0,20,0"/>
-
-                    <TextBlock Text="Duration:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
-                    <TextBlock Text="{Binding CurrentHealth.StreamDuration}" Style="{StaticResource YtLabel}"
-                               Foreground="White"/>
-
-                    <TextBlock Text="{Binding CurrentHealth.HealthMessage}" Style="{StaticResource YtLabel}"
-                               Foreground="#e94560" Margin="20,0,0,0"/>
-                </StackPanel>
-
-                <!-- Resolution dropdown: far right -->
-                <ComboBox Grid.Column="2" Style="{StaticResource YtComboBox}" MinWidth="150"
-                          ItemsSource="{Binding QualityOptions}"
-                          SelectedItem="{Binding SelectedQuality}"
-                          DisplayMemberPath="Label"
-                          ToolTip="{Binding ResolutionHelp}"
-                          IsEnabled="{Binding IsOffline}"/>
-            </Grid>
-        </Border>
 
+        <controls:BottomBar Grid.Row="3"/>
         <!-- ═══ OVERLAY: Settings / Bug / Feature / About ═══ -->
         <Grid Grid.RowSpan="3"
               Visibility="{Binding IsAnyOverlayOpen, Converter={StaticResource BoolToVis}}">

MainWindow.xaml.cs

@@ -291,16 +291,6 @@ public partial class MainWindow : Window
         e.Handled = true; // the button's right-click context menu must not fire
     }
 
-    private void GearButton_Click(object sender, RoutedEventArgs e)
-    {
-        if (sender is Button { ContextMenu: { } menu } button)
-        {
-            menu.PlacementTarget = button;
-            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
-            menu.IsOpen = true;
-        }
-    }
-
     private void BackToAbout_Click(object sender, RoutedEventArgs e)
     {
         if (DataContext is ViewModels.MainViewModel vm)

Themes/Controls.xaml

@@ -1,5 +1,6 @@
 <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    xmlns:Helpers="clr-namespace:ytLive.Helpers">
 
     <!-- Base button style -->
     <Style x:Key="YtButton" TargetType="Button">
@@ -631,4 +632,15 @@
         </Setter>
     </Style>
 
+    <!-- Value-to-visibility converters, promoted from MainWindow.Window.Resources
+         so extracted UserControls can resolve them (AGENTS: controls must not
+         reach into a window's own resources; they share the app-level theme). -->
+    <BooleanToVisibilityConverter x:Key="BoolToVis"/>
+    <Helpers:InverseBoolToVisibilityConverter x:Key="InverseBoolToVis"/>
+    <Helpers:NotNullToVisibilityConverter x:Key="NotNullToVis"/>
+    <Helpers:NullToVisibilityConverter x:Key="NullToVis"/>
+    <Helpers:HiddenBoolToVisibilityConverter x:Key="HiddenBoolToVis"/>
+    <Helpers:EnumToBoolConverter x:Key="EnumToBool"/>
+    <Helpers:AllTrueToVisibilityConverter x:Key="AllTrueToVis"/>
+
 </ResourceDictionary>

ViewModels/index.md

@@ -51,7 +51,11 @@ Progress (Commit N/12 · tag):
 - [x] **Commit 9/12 · `refactor-commit-9`** — **Streaming** → `MainViewModel.Streaming.cs`
 - [x] **Commit 10/12 · `refactor-commit-10`** — **Chat** → `MainViewModel.Chat.cs`
 - [x] **Commit 11/12 · `refactor-commit-11`** — **Overlays** → `MainViewModel.Overlays.cs`
-- [x] **Phase 1 complete:** core `MainViewModel.cs` split into 10 functional partials (1,890 → 758 lines). Phase 2 (splitting `MainWindow.xaml` into UserControls) not yet started.
+- [x] **Phase 1 complete:** core `MainViewModel.cs` split into 10 functional partials (1,890 → 758 lines).
+
+**Phase 2 — `MainWindow.xaml` split into UserControls** (new `Controls/` folder, namespace `ytLive.Controls`):
+- [x] **Commit 12 · `refactor-commit-12`** — **BottomBar** → `Controls/BottomBar.xaml(.cs)` (gear menu + stream stats + quality dropdown; `GearButton_Click` moved to the control's code-behind).
+- [x] **Commit 13 · `refactor-commit-13`** — **HealthBanner** → `Controls/HealthBanner.xaml` (Row 1). Also promoted the 7 value↔visibility converters out of `MainWindow.Window.Resources` into `Themes/Controls.xaml` so extracted controls can resolve them (app-level, not window-level). Pending: TopBar, left scene/chat panel, preview pane, overlay host.
 
 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.