- Source.IsBrandLogo persisted (additive migration); layer healed on load, removal blocked
- Image stored as an asset; settings keep the asset id and file name
- App Settings: Brand Logo file field with Browse
- Default placement top-left; per-scene eye uses the existing element visibility
Test: BrandLogoTests; layout/background tests pass (34). Not pushed.
The transition started with no from-frame, so BlendFrame returned the new scene at once.
Start now requests a capture and the frame pump supplies its last output on the next tick.
Test: TransitionFadeTests. Docs: ai.md, TASKS.md.
Not pushed.
The manifest the Store route needs, and a real package built from it.
Packaging/Package.appxmanifest is a full-trust packagedClassicApp: EntryPoint
Windows.FullTrustApplication, uap10:TrustLevel=mediumIL,
uap10:RuntimeBehavior=packagedClassicApp, the rescap runFullTrust capability, and
webcam + microphone DeviceCapabilities. That combination is what lets the packaged
app launch the bundled ffmpeg as a child process and write to the user's profile;
an appContainer package would virtualise the recordings folder instead. x64 only,
en-US only (policy 10.7).
Packaging/Assets/ carries the four tiles the packer requires, generated from the
app's own Assets/llamacasty-logo.jpg by scripts/make-store-logos.py - listing art
and app art cannot drift.
scripts/package-msix.sh publishes Release win-x64 self-contained into
artifacts/msix-stage (a RID-less publish would copy every RID's ONNX native),
stages the manifest as AppxManifest.xml + Assets, and runs the Windows SDK's
makeappx. MSIX_PFX/MSIX_PFX_PASSWORD sign a package for a local test install; the
Store signs submissions. artifacts/ is gitignored.
First real package: artifacts/LlamaCasty.msix, 159 MB, 509 files, 'Package
creation succeeded'.
Schema traps found by packing (makeappx reports one error at a time):
Square310x310Logo and Wide310x150Logo are NOT uap:VisualElements attributes - they
live on uap:DefaultTile.
Guard: StorePackagingTests.The_package_manifest_declares_full_trust_camera_and_
microphone - identity/architecture, the full-trust application element, the three
capabilities, no appContainer VALUE (not the file text: the manifest's own comment
says the word), en-US only, and every referenced logo present.
Full suite 438/438, 0 warnings. Cold-start smoke test after the Velopack removal:
MainWindow loaded, no exceptions.
The creator's ruling (2026-09-27) is Store MSIX + Store IAP, so Microsoft delivers
the updates and the in-app updater is gone rather than parked. This is a
COMPLIANCE action, not cleanup: the Velopack bootstrap downloaded and executed a
payload, which Store policy 10.2.2 does not permit.
Three edit sites, as planned: the PackageReference in ytLive.csproj, 'using
Velopack;' in App.xaml.cs, and the bootstrap block. The self-hosted DigitalOcean
update-URL droplet dies with it.
Guard: ytLive.Tests/StorePackagingTests.cs - the ONE test asserts the app project
references no updater package (Velopack/Squirrel/NetSparkle/AutoUpdater/WinSparkle)
and that no app source file uses the updater API. The check matches CODE (a using
directive, a type usage), not a bare word, so a file's prose may still name what it
deliberately does not do.
Smoke-tested after the removal: MainWindow loaded, 0 exceptions in startup.log.
Full suite 437/437, 0 warnings.
The creator (2026-10-09): 'we need some sort of log-rotation so that we don't
inadvertently fill up a user's drive.' startup.log was uncapped - 23MB and growing
every few seconds, because FfmpegEncoder logs every non-progress ffmpeg stderr line.
The policy lives in a new Helpers/LogRotation.cs as a pure function over a path
(RollIfNeeded(logPath, maxBytes, retainedFiles)), so AppLog's 156 call sites keep
their surface and the rule is testable on its own. At 5MB the live file rolls to
startup.1.log and one rolled copy is kept - the FILE SET is bounded, not just the
live file, so a long stream cannot grow the log without limit. A failed rotation
degrades to the old behaviour instead of taking the app down.
Pattern reference (cited): Serilog's file sink pairs fileSizeLimitBytes (the cap)
with retainedFileCountLimit (how many rolled files to keep) -
https://github.com/serilog/serilog-sinks-file
Guard: ytLive.Tests/AppLogRotationTests.cs - the ONE test drives the real
AppLog.Write against a temp dir (two internal seams: PathOverride, MaxBytes) and
asserts the roll, the fresh live file, and that after a SECOND roll the directory
still holds exactly startup.log + startup.1.log.
Also fixed a stale catalog row: TASK 12 (master limiter) shipped 2026-08-15 and was
still marked 'Queued'.
The creator (2026-10-21), on Live -> Layers -> webcam -> Properties:
"why does the drop down under the web cam properties not show the same style for
the border color drop down list box?"
"one of the first things we did was define branding. We established look-and-feel
standards. And yet you keep ignoring these and I'm wondering why"
WHY IT WAS MISSED - the answer the creator is owed.
The TASK 58 sweep had already walked the whole app for un-themed controls and the
border picker STILL was not themed, because the sweep looked for control TYPES
(ComboBox / CheckBox / TextBox) carrying no theme style - and the border picker was
NONE of those. It was a "..." Button whose Click handler built a ContextMenu of
swatches in code. It was never in the sweep's scope, and PropertiesStyleTests.cs
(a type-based guard) could not see it either. A picker that LOOKS like a drop-down
is invisible to a type-based audit; the guard has to ask "is this the app's widget?".
WHAT CHANGED
- The picker is now the app's YtComboBox - the widget the Display and Font pickers
wear - bound to the palette (SelectedElement.BorderColorOptions) with its selection
bound by VALUE (SelectedItem -> BorderColorEntry), because WPF's SelectedValue
matching is ordinal and the palette mixes #FFFFFF and #e94560.
- The closed box shows the swatch + the colour's NAME; the rows show swatch + hex +
name (the rows the creator approved in TASK 60). A ComboBox cannot do that with one
ItemTemplate - WPF copies it into the read-only SelectionBoxItemTemplate - so
Helpers/ClosedBoxTemplateSelector.cs picks by the ContentPresenter's templated
parent: the ComboBox for the closed box, the ComboBoxItem for a row. Verified
against WPF with a throwaway probe, not assumed.
- The swatch is painted by the THEME (Helpers/HexToBrushConverter.cs, registered as
HexToBrush) - the hand-painted SolidColorBrush(Color.FromRgb(...)) in the old
click handler was the exact anti-pattern the theme forbids. The swatch also carries
a 1px #2a3a5e border now, so black and dark swatches are visible on the dark menu
(the follow-up TASK 60 left open).
- The hex field stays (60px, editable): a colour outside the palette can still be
typed, and the drop-down then carries that hex as a NAMELESS entry ("no name" is the
honest answer). The palette's name moved out of TASK 62's TextBlock into the
drop-down's closed box.
- The hand-built menu, its ContextMenu/MenuItem/SolidColorBrush code and
WebcamBorderColorPicker_Click are gone.
MODEL: SceneElement.BorderColorName -> BorderColorEntry (the palette entry for the
current hex, with its name; setting it writes the hex back) + BorderColorOptions (the
palette plus the custom entry), both raised when BorderColor changes.
BorderColorPalette gains EntryFor(hex) and OptionsFor(hex); NameOf delegates.
Guards: ytLive.Tests/BorderColorPickerTests.cs (the ONE test for this change - the
model, the panel, and the REAL widget: with the app's theme style and the panel's own
templates the closed box names the colour and the rows show the hex AND the name).
The TASK 60 guard (BorderColorPaletteTests) was updated because the mechanism it
asserted - a code-built menu - no longer exists; it now guards the new wiring (the
drop-down is bound to the palette and neither the panel nor the code-behind carries a
second list of colours).
Full suite: 435/435 passed, 0 warnings.
The creator (2026-10-21), on Live -> Layers -> webcam -> Properties:
"the Y and H boxes under webcam properties should be the same width as the X and W
boxes and those widths should be fixed to accomodate the max number of possible
digits providing the geometry values"
"also the border color drop drown box content should also include the name of the
color next to the hex value as they in the drop-down list box"
TASK 61 - one fixed width for the four geometry fields.
The row is a DockPanel, and WPF sizes an element to its CONTENT unless it is told
otherwise, while the LAST child of a DockPanel fills the remaining space. So X/W (not
last) were as wide as their text and Y/H (last) stretched across the row - two widths
for the same kind of field. Now all four carry Width="44" and the rows set
LastChildFill="False" (without it the last field ignores its own Width and fills anyway).
44px is the measured width of "-1920" in the app's font at 11px (the largest geometry
value - the master frame is 1920x1080 - plus a sign) plus the field's padding and
border. Docs: https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.dockpanel.lastchildfill
The guard MEASURES the widest value with WPF's FormattedText instead of asserting a
magic number, so a font change cannot silently make the field too narrow:
https://learn.microsoft.com/en-us/dotnet/api/system.windows.media.formattedtext
TASK 62 - the border field names its colour.
SceneElement.BorderColorName carries the palette's name for the current colour
("Crimson") and is raised when the colour changes; it is EMPTY for a custom hex the
creator typed, because "no name" is the honest answer. BorderColorPalette.NameOf
changed to match (it used to fall back to the hex itself; the TASK 60 test assertion
was updated with it). The hex field keeps a fixed width (60) so the name sits right
next to the hex instead of drifting to the row's far edge - the same trap as TASK 61.
Guards: ytLive.Tests/GeometryFieldWidthTests.cs, ytLive.Tests/BorderColorNameTests.cs
Full suite: 435/435 passed, 0 warnings.
The creator: "under Live->Layers->webcam->Properties->border color: in the drop
down box, the #hex values are good, but add a corresponding color name/label next
to the value."
Each row now reads "#e94560 Crimson" - the hex stays exactly as it was, the
colour's name goes next to it (dimmed #a0a0b0 so the hex reads first), and the
tooltip becomes "Crimson (#e94560)".
The 14 colours were a hard-coded string[] inside the click handler - a list of
bare strings cannot carry a name, and a list hidden in UI code cannot be asserted
on. They now live in Models/BorderColorPalette.cs: NamedColor(Hex, Name) +
BorderColorPalette.All (the single source of truth) + NameOf(hex), which answers
case-insensitively and falls back to the hex for a colour outside the palette.
The picker builds its menu from the catalogue and no longer knows any colour by
heart.
The names are chosen not to collide - the palette has two greens, two blues and
two warm colours: #00FF00 is Lime and #22c55e Emerald, #0000FF is Blue and
#3b82f6 Azure, #FF8800 is Orange and #f59e0b Amber.
Guard: ytLive.Tests/BorderColorPaletteTests.cs - every entry valid + named, no
hex or name repeated, the 14 legacy colours all still offered, NameOf answers,
and the old list is gone from the handler. 433/433 green, 0 warnings.
The creator's ruling on the webcam's properties: a "Shape" title above the
Mirror/Rect row; the drag hint indented under that row "to show parentage";
the same for Geometry, Border Color, Border Thickness; Remove and Blur indented
under Background; Strength indented under Blur.
One rule covers it: a title owns its content and the content is indented one
level (10px) under it - two levels where a title is itself nested (Strength
under Blur under Background). The titles are SemiBold 11px #a0a0b0 like the
ones already there.
The shape also stops being a toggle button that shows the NEXT action ("Round"
when the camera was a rectangle) and becomes a CHOICE: two segment options,
Rect | Circle, with Rect selected by default - which is what the creator asked
for ("Rect should be selected as a default if none exists"). The old
ShapeButtonText is gone.
The mutual exclusion lives in the MODEL: IsRectShape/IsRoundShape on
SceneElement, each setter flipping the shape through ToggleClipShape() (so the
pre-round rect is still stored/restored) and always re-raising, so a refused
write - the vertical Chat layout is rect-only (TASK 57) - makes the UI snap
back instead of sticking. Deliberately NOT a WPF RadioButton group: a group
unchecks its siblings by setting IsChecked in code, which makes WPF drop the
binding (stackoverflow 7376373; the same trap measured in 50980687/57275046).
The Circle option stays hidden where CanToggleClipShape is false, so the circle
is still not offered in the vertical Chat layout.
Guard: ytLive.Tests/PropertiesHierarchyTests.cs - the model half (Rect by
default, pick circle, pick rect, the locked Chat layout refuses the circle) and
the panel half (the Shape title owns both options, the circle is the gated one,
the hint is indented and follows the row, every titled block's content is at
10px, Strength at 20px). 432/432 green, 0 warnings.
The creator asked why the Stream Alerts "Display" drop-down was not in the same
style as the other drop-downs. It was never given the theme's YtComboBox style -
only a hand-painted Background/Foreground. Setting colours changes the paint, not
the template, so WPF still drew the light system ComboBox (grey border, system
arrow, white popup list) on top of the dark panel. The chat Font drop-down was a
copy of the same mistake, and every check box was the light system one.
The sweep of the whole properties panel (then the app):
- ComboBox x2 (chat Font, alert Display) -> YtComboBox, hand-painted colours gone
- TextBox x16 in the properties panel -> YtTextBoxCompact (new, BasedOn YtTextBox:
11px / padding 4,2 - the panel is dense, the full 13px box would double it)
- CheckBox x2 (chat) + x3 (preview broadcast) + x1 (socials dialog) -> YtCheckBox
(new: a 14x14 rounded box + tick path, accent fill when checked)
- the layer-rename field -> YtTextBoxCompact via BasedOn, still borderless
- buttons, pills, sliders: already themed, untouched
The sweep also killed a typo'd foreground (#e0d0e0 for #e0e0e0) and the only
remaining hand-painted colour is the deliberate dimming of the two read-only path
fields.
Guard: ytLive.Tests/PropertiesStyleTests.cs (the ONE Good Dog test) parses the app
XAML and fails if an unstyled drop-down, check box or properties field comes back.
431/431 green, 0 warnings.
The creator's locked table (2026-10-17) gives the Chat scene its own rules in
the 9:16 tier: RECT ONLY - the circle option is not offered - and a size that
is either the normal small tile or ENLARGED to fill one whole 607x540 area
(top or bottom). Unit 1 shipped the per-scene placement; this unit is the Chat
scene's own variant of it.
The rule lives on the MODEL, not on the button:
- Models/SceneElement.cs: ClipShape and ToggleClipShape() are now virtual.
- Models/WebcamSceneConfig.cs: VerticalShapeLocked (set per scene by the VM)
OVERRIDES the ClipShape property, so no writer can slip a circle in - the
toggle, the Shape button and the placement swap all go through it. The lock
is cleared BEFORE the 16:9 layout comes back, so the desktop shape returns.
- ViewModels/MainViewModel.Webcam.cs: CanToggleClipShape (the circle is NOT
offered in the vertical Chat layout - the Shape button disappears, it is not
merely greyed out), IsChatSceneCamera, ResizeWebcamInVerticalTier.
- Models/VerticalCameraLayout.cs: FillsArea (the "enlarged" state, derived -
no new column) and SizeFor - the Chat camera's TWO sizes, the tile or the
whole area, whichever is nearer the requested width, so the resize handle
has two detents instead of any size in between.
- An enlarged camera FILLS the area its centre is in (top or bottom), so
dragging it up/down swaps the areas.
- The Chat camera is auto-tiled like the Live one when the vertical tier is
picked - otherwise the vertical chat stream has no camera at all.
- Controls/PreviewPane.xaml.cs: the resize routes through the VM; the drag
assigns, lets the model clamp into the band, then snaps (so the enlarged
camera can be dragged from the top area to the bottom one).
Test: ytLive.Tests/VerticalChatCameraLayoutTests.cs - the ONE Good Dog test for
the unit: the vertical tier is picked -> the Chat camera comes into the band as
a small RECT tile -> the circle option is not offered and cannot be set even on
the model -> dragged up and enlarged it fills the TOP area exactly -> back to
16:9 the desktop layout is restored exactly and the circle option is offered
again. 430/430 tests pass, 0 warnings.
Research (the creator's table is the established practice, not our invention):
- Streamlabs' vertical guide: "splitting the screen in half horizontally,
placing the camera feed in the top half and the main content on the bottom
(or vice versa) may be the bet", and a just-chatting vertical wants the
camera "to take up most of the screen"
(streamlabs.com/content-hub/post/overlays-vertical-and-horizontal-streaming)
- Bloopbot's vertical overlay docs describe the same per-layer model we use at
scene granularity: "move or resize a layer on Vertical and it stops being
Auto-placed. It keeps the place you gave it, and the horizontal layout is not
touched" (bloopbot.com/docs/vertical-overlays-twitch-dual-format) - our
swap-at-tier-change, stored per scene.
- Landmine recorded: "about the bottom 560 px of the vertical video can be
covered by Twitch's chat and player controls on phones" (Bloopbot) - the Chat
camera's enlarged BOTTOM area may be half-hidden by the platform chrome;
TASK 53's safe-zone work decides that.
Memory in the same commit: ai.md (the Chat rules, the shape lock, the tests),
TASKS.md + TASKS/task-57-vertical-camera-layout.md (TASK 57 complete), HANDOFF.md,
MyMistakes.md (3 recipes: lock the model property not the UI button; two detents
for a discrete size set; the edit tool cannot match an oldString with an em
dash), Models/ViewModels/Controls index rows.
The vertical tier is a centred band crop of the SAME 1920x1080 master (band x
656.25, w 607.5, h 1080), so the 16:9 camera placement (x~1408) falls outside the
cropped window and the creator is simply not in the vertical stream. Each scene
now keeps its own vertical position, size and shape; switching back to 16:9
restores the desktop layout exactly (the creator's locked table, 2026-10-17).
Geometry only - NO render-path change. The preview and the compositor both read
the element's own X/Y/W/H + ClipShape, so the tier switch swaps the LIVE geometry:
- Models/VerticalCameraLayout.cs (new): the pure math - the band, its two 607x540
areas, the six spots (top/bottom x left/centre/right), the 32px inset and the
270x152 default tile (480x270 in the 1080x1920 output) in the bottom-right spot,
the corner the 16:9 default webcam uses.
- Models/WebcamSceneConfig.cs: the vertical placement lives in seven additive
columns (VerticalX/Y/Width/Height/ClipShape/RectWidth/RectHeight; NULL = "this
scene has no vertical placement yet"). The 16:9 layout stays in the old columns
and is parked in the transient Landscape* fields while the vertical tier is
live; Begin/EndVerticalLayout + CommitLiveLayoutToVertical do the swap. The
X/Y/W/H overrides clamp every write into the band - outside it the camera is
invisible in the vertical output.
- Models/SceneElement.cs: X/Y/Width/Height became virtual so the derived element
constrains every writer (drag, resize handle, typed fields) in ONE choke point
instead of three writers each re-implementing the rule.
- ViewModels/MainViewModel.Webcam.cs + .Streaming.cs: IsVerticalTier/VerticalBand,
ResolveVerticalCameraLayout(s) (the tier swap), MoveWebcamInVerticalTier /
SnapWebcamInVerticalTier (the six-spot snap, by the tile's centre),
EnsureVerticalCameraLayout; ApplyStreamQuality is the tier-change hook. The
Live scene gets its small tile automatically on the first vertical switch (the
vertical stream would otherwise have no camera at all); the other scenes keep
their 16:9 placement until the creator drags them into the band.
- Controls/PreviewPane.xaml.cs: the drag/resize route through the VM snap under
the vertical tier instead of free-floating over the master.
Controls/LeftPanel.xaml: the webcam properties gained a Geometry section
(X/Y/W/H) for the manual entry the creator asked for, bound to the LIVE
placement, gated on the VM's IsWebcamSelected (NOT SelectedElement.IsWebcam -
the TASK 51 test finds that panel by binding text and would match twice).
- The store: seven guarded ADD COLUMNs, the INSERT/SELECT extended, and the
X/Y/W/H/ClipShape columns stay the 16:9 layout - while the vertical tier is
live the save writes the parked values there and the live ones into Vertical*.
Test: ytLive.Tests/VerticalWebcamLayoutTests.cs - the ONE Good Dog test. The
vertical tier brings the Live camera INTO the band as a small tile; dragging it to
the top-right lands it top-right inside the band; back to 16:9 the desktop layout
is restored exactly (1408/778/480x270); both placements survive a save + reload.
Full suite 429/429, 0 warnings. LayerReorderPersistenceTests.RealMouseDrag fails
ALONE on a clean tree in this environment - pre-existing flake, proven by stashing
this work, not a regression.
Derivative work: OBS has no built-in per-aspect-ratio layout storage - the
maintainers' answer is "create a second scene and add the scene you want to send
as source" (obsproject.com/forum/threads/161307) - and Streamyard's dual-aspect
guide says the same ("no built-in way to store separate layouts per aspect ratio",
so you rely on manual workarounds and plugins):
https://streamyard.com/blog/dual-aspect-ratio-streaming-tool
Our per-scene, per-tier stored placement, resolved on the tier change, is the
step past both.
Memory in the same commit: ai.md (new section), TASKS.md + TASKS/task-57-*.md
(Unit 1 shipped, Unit 2 = the Chat scene still open), HANDOFF.md, MyMistakes.md
(the per-tier geometry-swap recipe, the binding-text panel trap, the store's
webcam-identity rule) and the Models/Services/ViewModels/Controls index rows.
The suite failed Stats_ReportRealRendersAndDistinctWebcamFrames_NotJustPaddedSubmits
with "Collection was modified; enumeration operation may not execute" at its OWN
log.Any(...) line (FramePumpTests.cs:606): the test handed FramePump a plain
List<string> and enumerated it from the test thread while the pump reported stats
from its loop thread — pacingDelay is Task.Yield(), so the loop really is concurrent.
Production passes the thread-safe AppLog, so the app was never involved.
It passed 3/3 in isolation, which is exactly how a data race presents as a
load-sensitive flake. The trigger: the previous commit ("Per-element composite timing
+ scene dump") added log lines emitted FROM the pump thread, raising the collision
rate from rare to routine — a latent race in the old test, promoted by the new
traffic.
Fix: ConcurrentBag<string> (enumeration is a moment-in-time snapshot) for the sink,
2 call sites + the NewPump parameter. No app code touched.
Proof: full suite 428/428 passed, 0 warnings (the run that surfaced the failure was
before the fix; the same failure has not recurred).
Docs in the same commit: MyMistakes.md — "A 'known failure' label without a recorded
cause = a bug on life support" gained this second instance, with the rule that a
test failing ONLY under load means a shared mutable collection on the producer's
thread, not a retry.
The cadence work ended with a question the log could not answer: the compositor
manages 6.8 composites/s at ~141ms while the 10:03 take did 29-34ms on the "same
scene shape" (full-render split=0 elements=6 dynamic=5). Nothing in the stats line
said WHICH of the six elements cost what, and nothing recorded the scene itself, so
the two takes could only be compared by eye. This closes that gap and nothing else:
no fix is attempted until a real take names the culprit.
- Services/Compositor/CompositeTimings.cs (new): per-window collector.
Add(stage, ticks) accumulates; Describe(renders, minMs = 0.1) prints the averaged
breakdown slowest-first, dropping sub-0.1ms noise.
- SceneCompositor.Render / CompositeLayers / BakeStaticBase / BlitBakedElement /
BlitCachedLayer + SceneGraph.GetBakedBase: trailing optional CompositeTimings?
Every stage is timed (backdrop, base, flash, social, ticker, zoom, scale, overlay,
bake backdrop, bake overlays) and EVERY element gets its own entry keyed by
z-index + name ("#2 Webcam"), with the nested "raster" sub-stage recording the
paste-cache rasterize miss - the split between "re-samples every tick" and "slow
paste" without a second session. Bake-pass elements are prefixed "bake #..." so a
one-off rebake cannot masquerade as a per-composite cost. Callers that pass
nothing (thumbnails, existing tests) are unaffected and pay nothing.
- FramePump: owns the collector, threads it through RenderScene/RenderFull/
GetBakedBase/CompositeLayers, and logs "FramePump parts (N renders/5s): ..." once
per 5s window beside the stats line (averaged per render, so it compares directly
with "avg render"), then resets it. Also dumps the scene - "FramePump scene dump:"
header plus one line per element (z-index, name, kind, source type, visibility,
rect, opacity, clip) - at pump start and on every scene change.
- One Good Dog integration test (ytLive.Tests/CompositeTimingTests.cs): a real
composite of a full-canvas element plus a 64x64 one through the real collector
must rank the full-canvas element first, carry the raster sub-stage and the fixed
stages, and the dump must name both elements with z-index/type/rect and echo the
split point.
Derivative work (AGENTS.md): OBS's answer to "which source is slow" is the Source
Profiler - average execution time of each source's tick and render functions
(https://docs.obsproject.com/reference-libobs-util-source-profiler, util/profiler.h).
Same shape here: one timer per element per composite, reported as an average, plus
the stage split this case needs.
Docs in the same commit: ai.md (new subsection "Per-element composite timing + scene
dump", the closed gap corrected in "Frame cadence"), Services/index.md (new file row
+ FramePump/SceneCompositor rows), TASKS.md (unit marked shipped, next = creator
take), HANDOFF.md (rewritten: unpushed commit, next step, verify.sh whitelist hole).
Also recorded this session (from the creator): the launch command is
`dotnet run -c Release` - Release is the DEFAULT, Debug only when explicitly named,
and perf takes must read Release. ai.md -> Run updated.
Full suite 428 tests, 0 warnings; the only failures are the known audio env flakes
(both pass in isolation). Scope check passed.
- Model: Google's official MediaPipe Selfie Segmenter (landscape, Apache-2.0 per model card),
converted to ONNX by tools/selfie-seg/convert_tflite_to_onnx.py (custom op
Convolution2DTransposeBias -> ConvTranspose) and verified against MediaPipe's own runtime
(verify_against_mediapipe.py: max |diff| 5e-5, 100% binary agreement). Embedded resource, 430 KB.
- Services/BackgroundEffects: IPersonSegmenter seam, OnnxPersonSegmenter (onnxruntime 1.31.0 CPU,
never throws), BackgroundEffectProcessor (None passthrough, Remove = alpha mask). Not wired yet.
- Tests: Remove integration test (fake segmenter) + bundled-model contract test vs MediaPipe
reference mask. Full suite 407/408 — the one failure is the documented interactive-desktop flake
RealMouseDrag_OnTheLayerList_PersistsTheReorder (passed in the run before; code path untouched).
- Docs: ai.md reversal + section + licensing guard, THIRD-PARTY-NOTICES 11-12, TASK 51, indexes,
MyMistakes recipe, HANDOFF.
References: obs-backgroundremoval (approach only — ONNX Runtime on CPU, 2 threads; GPL-3.0, no code
used) https://github.com/royshil/obs-backgroundremoval ; MediaPipe image segmenter
https://ai.google.dev/edge/mediapipe/solutions/vision/image_segmenter
The zoom feature shipped without a task record while its index rows carried the
"TASK 51" label — which belongs to the webcam background effects (Remove + Blur).
For an honest catalogue and handoff:
- TASKS/task-52-zoom-box.md: feature provenance (creator-requested), the three
2026-10-08 corrections (loupe -> anchored capture over the full composite drawn
last -> never show the dim shading), shapes, implementation map, tests, DONE.
- TASKS.md: row 52 added (shipped); row 51 reworded — unblocked now that the
zoom build shipped.
- TASK 51 -> TASK 52 in Models/index.md, ViewModels/index.md, and the two code
comments that pointed at the zoom as "TASK 51".
- HANDOFF.md: pre-push readiness notes (5 commits ahead, push-safe).
Creator's final zoom correction: as the box is dragged, its capture region slides
under the dim rectangles and the box picks up the 55% black "div shading" inside
itself, because the VisualBrush samples the whole CanvasGrid and DimRects lived
inside CanvasGrid. The captured area must stay clear regardless of box position.
- PreviewPane.xaml: the DimRects ItemsControl is now a SIBLING of CanvasGrid
(above the composed content, below the ZoomBox), never a descendant — the zoom
source is shading-free by construction.
- ZoomBoxInteractionTests: structural invariant — DimRectsLayer is a direct
child of PreviewCanvas (not inside CanvasGrid) and renders below the ZoomBox.
- Side effect (correctness, not a bug): quality dims now also sedate the global
overlays outside the crop, matching "chrome outside the crop is dimmed".
Creator corrected the "loupe" zoom on 2026-10-08: the click anchors a fixed
capture region (box/2 centred on the click) and the box is a live 2x view of
that region — dragging the box never changes its content; it magnifies the
fully-composited frame (every layer, incl. webcam) and draws LAST (n+1).
Rectangle shape is 4:3 ("more of a 640x480 aspect").
- MainViewModel.Zoom.cs rewritten: ActivateZoom anchors CaptureX/CaptureY
(independently clamped); UpdateZoomMove relocates the box only; the per-frame
BuildZoomFrame/ZoomFrameBuilder path is gone.
- SceneCompositor: skips the active ZoomSceneElement in every layer loop and
BlitZooms it last via the new pure ZoomMagnifier (2x bilinear, temp snapshot
via ArrayPool, round clip).
- Preview: ZoomBox hoisted above CanvasGrid as a sibling; its brush samples the
whole composed preview at the fixed capture (2x).
- Tests: ZoomMagnifierTests (box-over-blue shows green capture at 2x incl. an
extra red "layer" — the loupe/backdrop-only regressions both fail it) +
round-clip; ZoomBoxInteractionTests rewritten (anchored capture, move-doesn't-
change-capture, 4:3/9:16/square). 404 pass, 2 known environment flakes.
Right-click now creates a transient ZoomSceneElement at z-index 1 whose pixels are a
genuine 2x magnified sample of the backdrop (live capture under art), composited into
stream/recording like any layer while the output crop stays the tier. All shapes are
centered on the click and clamped to frame; healed on load/scene-create, never persisted,
hidden from the layers list + element template (IsZoomLayer). BuildCompositorOptions is
now internal = always tier crop (test seam). ZoomFrameBuilder is a pure static sampler
(box/2 window centered on the box center, single-slot cache) proven by a banded-backdrop
test; LayerReorderPersistenceTests drag resolves rows by item since the collapsed zoom
row shifts container indices. Also books TASK 51 (webcam background Remove + Blur) and
syncs memory docs (HANDOFF, MyMistakes, indexes). Full suite: 405 passed, 0 warnings.
Right-click in the live preview now procs a box that is actually visible and
populated with the zoomed region, and each Zoom View Shape sculpts the box per
spec. OBS-style derivative: magnifier box shows the composited region and dims
the surroundings (same pattern as OBS "zoom" / preview region highlights).
Root causes of the invisible box (two WPF traps, recorded in MyMistakes.md):
- Empty <VisualBrush Stretch="None"/> used as an OpacityMask paints nothing,
so the mask alpha is 0 and the WHOLE box (border included) went transparent.
- ZoomBox lived inside CanvasGrid while its VisualBrush sampled CanvasGrid — a
circular reference WPF renders as nothing. Hoisted ZoomBox to a sibling of
CanvasGrid inside a new PreviewCanvas wrapper (same 1920x1080 space).
Shape semantics (MainViewModel.ActivateZoom):
- Circle: square, click point = center.
- VerticalRectangle (phone): tall 9:16, click point = top-left corner.
- HorizontalRectangle (tablet): wide 16:9, click point = top-left corner.
- Boxes stay fully inside 1920x1080 via Math.Clamp.
UI: ZoomRectOutline/ZoomCircleOutline shapes replace the square Border;
circle clips the box to an EllipseGeometry; brush Visual released when inactive.
Zoom View Shape dropdown now uses the standard YtComboBox style.
Test (Good Dog rule, one integration test): ZoomBoxInteractionTests verifies
aspect/anchoring/clamp per shape and the matching outline+clip in the real
MainWindow. Full suite 404 passed, 0 warnings.
Memory: HANDOFF.md zoom state updated; WPF VisualBrush traps appended to
MyMistakes.md.
A composite splits into four horizontal row strips across four DEDICATED
background threads; the calling thread takes a strip too (so four workers
never mean five-way oversubscription), and anything under 64 rows runs
inline. BlitContentRaw, BlitBakedElement and BlitOverlay now fan out.
Output is byte-identical — strips already partitioned by row.
The demotion deliberately does NOT come from Parallel.For. The pool is
shared, so Thread.CurrentThread.Priority = BelowNormal inside it leaks
into every unrelated work item that thread later runs — a full test run
after trying it broke AudioPipelineTests.Mix_HonorsProviderGains_AndGameMute_
KillsTheLoopback. Established guidance agrees: use your own producer/consumer
queue with your own Threads and set their priority yourself
(https://stackoverflow.com/questions/524483/net-backgroundworker-objects-thread-priority,
https://stackoverflow.com/questions/1578599/c-sharp-lower-thread-priority-in-thread-pool).
Helpers/StripPool.cs is that queue. Four threads is the measured sweet
spot: fewer leaves render over budget, more steals cycles from the game
and the encoder and made render worse.
The scaled blit's column LUT moves from a shared static buffer to
ArrayPool<float>.Shared with a finally — a single static buffer is a data
race the moment strips run in parallel.
Gate: SceneCompositorTests.StripParallel_RepeatedRenders_AreByteIdentical —
8 renders of a scaled round webcam + mirrored image + master-sized flash over
a short backdrop must be byte-for-byte identical, and must differ from a
backdrop-only render so it cannot pass vacuously. It caught a loop-variable
capture (new Thread(() => Worker(i)) saw i == Workers) that crashed the test
host on the first run.
The creator is DHH and lipreads their own recordings, so a webcam that
judders is an accessibility defect, not a polish item. Take
ty-20261005-1001-821-0001.mp4 holds 25.6 distinct webcam images/s against
the camera's 30fps with 281 gaps of 50-100ms - roughly one hitch in five -
in a file that muxes flawlessly. Nothing in the app could see that: rawvideo
carries no per-frame timestamps (ffmpeg stamps by ARRIVAL at the declared
60fps), and the stats line divided every average by the number of frames
SUBMITTED, which deadline padding always fills to the full target. So the
pump reported "300/300 frames, avg render 12.4ms" while producing 60
distinct composites.
Helpers/FrameCadence.cs is one pure counter fed from three points:
MediaCaptureFrameSource logs the device's own SystemRelativeTime stamps
against our arrival times (TryAcquireLatestFrame keeps only the LATEST
frame, so falling behind is silent by design), and FramePump logs the
distinct webcam Epoch values that reached a composite. Read together they
name the culprit - device/USB, our reader, or our compositor - instead of
guessing. Render/resolve/wait now divide by the real render count, and
"frames per 5s from R renders" is the duplicate-on-lag ratio stated
honestly.
An out-of-order timestamp counts as a frame but produces no gap and does not
become the next interval's reference, so one bad stamp cannot invent a
multi-second hitch twice.
Also corrects a stale ai.md line (the "webcam renders at ~18fps" figure
came from a different session and counted every newly rendered layer) and
re-records the background-removal ruling as permanently out. Records the
agreed-but-unbuilt Units 1-2, the no-fallback-camera ruling, and the
SetFormatAsync dead end found by probing the 19041 projection.
Suite 402/402, 0 warnings. The one red, LayerReorderPersistenceTests'
RealMouseDrag, fails identically on a stashed clean tree - it needs an
interactive desktop session this shell lacks.
Creator ruling: open in the upper-left of the screen with ~75px padding. The
restore path was placing the window below the fold.
RestoreWindowGeometry now ignores the saved position and calls the pure
TopLeftPlacement(workArea, w, h, padding): work-area origin + LaunchPadding
(75, in DIPs so it scales with DPI), clamped so the window is never pushed
off-screen. A window that fits stays wholly visible; one too big to fit falls
back to the work-area origin.
Size and maximized state are still persisted -- only position was dropped. The
size clamp is unchanged (saved values clamp to [MinWidth, work.Width], which is
why a saved 800x500 returns as 1366x768 per the XAML minimums).
The old clamp tolerated Left as low as work.Left - width + 120 and Top up to
work.Bottom - 80, ranges wide enough to leave the window almost entirely
off-screen while still looking like a successful clamp. A clamp that permits
the window to be unreachable is worse than none: it reads as a guarantee it
does not keep.
BroadcastPullOutTests is renamed ..._Window_Launches_TopLeft_... and now asserts
the constructor applies the derived placement for both an on-screen and a -99999
saved position. Placement math is covered by WindowPlacementTests as a pure
function needing no HWND.
Suite 395/395, 0 warnings.
root cause (proven, not inferred): contentDetails.boundStreamId on
liveBroadcasts.insert does NOT bind the broadcast. Our diagnostic reads
lifeCycle=created privacy=private autoStart=true bound=NONE
boundMatches=NO-BINDING | streamStatus=active
created is Google's "incomplete settings" state, so enableAutoStart has no
bound stream to fire from; close-out then 403s invalidTransition because
created -> complete is not a legal edge. A reusable stream accepts bytes for
a broadcast that isn't watching it, so a perfectly healthy 99MB RTMP session
is exactly what an unbound broadcast looks like -- every observable pointed
away from the binding.
Google's migration guide states the rule outright: a liveBroadcast must be
bound to exactly one stream before it can start, and is not bound at creation.
That was in the docs read during the original design and was not applied.
Shipped:
- BindBroadcastAsync -> POST liveBroadcasts/bind?part=id&id&streamId (no body),
called from PrepareAndStartLiveAsync right after CreateBroadcast, before the pump.
Failure is fatal to the session: an unbound broadcast can never go live, so a
live-looking UI over one is a lie.
- boundStreamId removed from the insert body, and the streamId parameter removed
from CreateBroadcast. A parameter that looks meaningful but cannot affect the
outcome is what made the misdiagnosis possible.
- Replaced CreateBroadcast_With_StreamId_Binds_Reusable_Stream_At_Insert, which
asserted the disproven behaviour and therefore laundered a guess into a
guarantee, with tests for the omitted field and the real bind endpoint.
Error messages (creator ruling 2026-10-04): bind failures are not all "check the
sign-in". Six documented reasons exist and only one is auth; BindFailureMessage
gives each its own text, and the fallback passes the raw reason through verbatim
so an unmapped reason stays greppable. liveBroadcastBindingNotAllowed matters
most -- it means our ordering is wrong, and a generic re-auth message would hide
a bug in our own code behind a plausible excuse. See MyMistakes.md.
ai.md: also corrects the TASK 44 claim that liveChatId is only populated once the
broadcast is live. The diagnostic shows it present while lifecycle is created.
That claim was inferred from a sample's active-status guard, which is not a spec.
Suite 395/395, 0 warnings.
The run I asked for came back with three alarming lines:
lifeCycle=? privacy=? recording=? bound=NONE boundMatches=NO-BINDING
autoStart=unset autoStop=unset liveChatId=none | streamStatus=active
Every single broadcast field was empty, and the stream half was fine. That
combination is the tell: not a failed request, a wrong nesting level.
liveBroadcasts.list returns a LIST wrapper, so the broadcast is at items[0]. I
descended into items for the stream and read the response root for the
broadcast, so every lookup missed, and BoundMatches — handed a null it could
not distinguish from a real null — reported a confident NO-BINDING. The
diagnostic invented the bug it was written to find. Three lines of fabricated
alarm on the one run that was supposed to produce evidence.
Two fixes, and the second is the one that matters:
FirstItem() descends into items[0] for both halves, and returns default when
there is genuinely no item.
The line now prints boundMatches=unread when the broadcast could not be
read at all, so an absent parse degrades to "I don't know" instead of a
verdict. A diagnostic that guesses is worse than no diagnostic: this one
would have sent me off to rebuild a binding that may well be correct.
Test guards the regression: FirstItem_DescendsIntoTheListWrapper_AndReports-
AbsenceHonestly, including the empty-items and missing-items cases. Suite
390/390, 0 warnings.
Credit to the run for catching it. What it did establish, from the half that
worked: streamStatus goes ready -> active about 30s into the push. So the
ingest registers as active server-side, which combined with the 99MB muxed
yesterday means the stream half is verified healthy end to end. The broadcast
half needs one more run to say anything.
The logs answered the question and closed off a whole branch of investigation.
The long run: broadcast inserted 14:17:04.577, ffmpeg to
rtmp://a.rtmp.youtube.com/live2/5f6z-... at 14:17:05.686, and ffmpeg's own
muxing summary at 14:18:56.473 reads
video:101229KiB audio:1419KiB muxing overhead: 0.202949%
~99MB of real video plus audio over 112s, which is what 8000+128 kb/s is
supposed to produce. No socket error, no 4xx from ingest, no reconnect. And the
broadcast still never left `ready`; close-out 403'd invalidTransition again. The
8s run behaved the same way, so "YouTube needed longer" is disproven — 112s is
longer.
So the RTMP path is provably healthy. That is the finding worth keeping: it
kills the entire "the push is broken" theory, which is where this had been
heading for a week. The break is between ingest being accepted and the broadcast
being told to start.
Which puts the binding in frame, and the app was structurally blind to it.
Google documents contentDetails.boundStreamId and says enableAutoStart fires
"when you start streaming video on the bound live stream" — both valid on
insert, neither restricted against reusable streams. But the migration guide
also says a broadcast "is not bound to any streams at the time that it's
created", and the failure that produces is invisible from the RTMP side
precisely because a reusable stream will happily accept bytes for an unbound
broadcast. Ingest succeeding proves nothing.
Hence LogBroadcastDiagnosticsAsync, riding the existing health poll rather than
adding a timer. One greppable line: lifecycle status, privacy, recording,
boundStreamId *compared against the stream id we are actually pushing*
(BoundMatches: yes / MISMATCH / NO-BINDING / unknown), boundStreamLastUpdate-
TimeMs, autoStart/Stop, liveChatId presence, the stream's own streamStatus and
activeLiveChatId, and the CDN settings we declared.
Deliberately self-limiting: _broadcastSeenLive latches on live/liveStarting so
the diagnostic shouts only while the broadcast is stuck and goes quiet once it
is healthy. A permanent per-tick log line would be noise; this is the opposite.
One test, per the Good Dog rule: BroadcastBindingTests pins the matrix and
specifically pins `unknown` when there is no stream id to compare against, so a
missing expectation can never be misreported as a match — that is the failure
that would make this diagnostic lie.
Suite 387/387, 0 warnings.
Startup took 44s and 42 of them were one line. Measured from startup.log:
OnStartup 08:42:59 -> MainWindow loaded 08:43:43, with the whole gap inside
LoadLayout, ending at
TRAX: failed to load '\\192.168.50.86\llamaVault\Assets\Music\...':
The network path was not found. (0x80070035)
LoadTrax called MusicPlayer.Load synchronously on the UI thread, and
new MediaFoundationReader(path) does not fail fast on a dead SMB session — it
burns the full ARP/TCP/SMB timeout and only then throws. The NAS had moved to
.87 after the power outage, so an unreachable path became a 40-second frozen
window on every launch.
The rule, from the creator: a probe may time out; a bind should return
immediately. Only one side of that is achievable here, and the reason matters —
an unreachable UNC path has no fast-fail at all, so probing it on the calling
thread is the worst possible probe. (A device open is the opposite: it normally
fails fast on a sharing violation, which is why this bug is network-specific.)
So: IsTrackReachableAsync runs the probe on a thread-pool thread under a
Task.WhenAny ceiling (TraxProbeBudget, 2s) and treats offline/missing/slow as a
normal state rather than an error. Only a probe that passed gets the real bind,
and that bind deliberately stays on the UI thread alongside every other
MusicPlayer mutation — moving the whole load off-thread would have introduced a
race against PlayTrax/PauseTrax that does not exist today. The orphan probe
thread stays parked until SMB gives up; it is not the thread anyone waits on.
One test, per the Good Dog rule: TraxProbeTests.
AHangingProbeIsAbandonedAtTheBudget_AndReportsOffline stands in a probe that
never returns and asserts the caller is released and told "offline". Drop the
ceiling and it fails on elapsed time — which is the frozen window returning.
Suite 381/381, 0 warnings.
The trap I hit twice today — a file-wide DoesNotContain matching the doc
comment that explains the ban — was possible because three tests each
hand-rolled their own File.ReadAllText + path-walker, two of them mine. Fixed
at the root rather than per-test: SourceAssert now owns path walking and
literal extraction, with Literal(memberName, params parts) and Scopes() that
assert on the parsed VALUE. Tests that genuinely assert structure (the #if
DEBUG arm in InstanceIsolationTests, the absence of a whole API in the
locator) still read the file themselves, because those claims cannot be
reduced to a value — the helper is for literal facts only.
Shipping the fix introduced two defects, both caught by the build: a method
named Path shadowed System.IO.Path and broke the error message that names the
missing file, and Literal(fileName, memberName) invited a call that silently
resolved to a nonexistent path. Argument order is now required-context-first
so a wrong path is visible at the call site.
Suite 380/380, 0 warnings. LayerReorderPersistenceTests.RealMouseDrag flaked
once mid-session with no ytLive instance running and passed in isolation and
on re-run — the environment flake already recorded in HANDOFF.md, not a
regression from this change.
force-ssl is gone from the requested scope. Its grant ("see, edit, and
permanently delete your videos, ratings, comments and captions") is a strict
subset of auth/youtube's ("Manage your YouTube account"), and Google's own
liveBroadcasts.insert reference lists auth/youtube as an accepted ALTERNATIVE
to force-ssl, so every endpoint this app calls — channels, liveBroadcasts,
liveStreams, liveChat, playlistItems — is covered by the one we keep. Two
consent lines became one, and one fewer scope to justify. Removing a scope
cannot narrow capability when the scope being kept is the broader of the two,
and there is no forced re-consent: a refresh token keeps the scopes it was
originally granted, so existing sessions are untouched.
The playlistItems change is NOT being made, and the map entry recommending it
was wrong. It came out of the verification hunt on the theory that public data
should not ride on user credentials. Walking the code kills it: ChannelStats-
Service is built with one HttpClient, and channels?mine=true on the same
service genuinely needs the session. Splitting it means a second unauthenticated
client PLUS a Google API key, since every YouTube Data API request needs a
credential and the call 403s without one. So the fix would ship a new
extractable, quota-abusable credential inside the binary to replace a token the
app already holds, buying zero verification-surface reduction (the data is
public, no scope involved) and zero correctness. Strictly worse. Recorded as a
do-not-do so it is not "helpfully" reintroduced later.
Test: ExactlyOneScopeIsRequested_AndItIsTheBroadOne asserts on the const's
parsed VALUE rather than scanning the file — a file-wide DoesNotContain
fails on the doc comment that names force-ssl to explain its removal, which is
the same trap I hit and documented earlier today in the locator test. Suite
380/380, 0 warnings.
Store policy 10.2.2 forbids dynamic code inclusion, and this was the only
third-party binary the app ever downloaded and ran. It had already failed in
production: the pin aged out of BtbN's 14-day retention and the download 404'd
on the creator's first real recording attempt (2026-09-01). Bundling kills
that failure class permanently and deletes the startup network dependency.
- scripts/fetch-ffmpeg.sh populates a gitignored ./ffmpeg from a pinned
month-end BtbN LGPL-shared artifact, SHA-256 verified before extraction,
idempotent, FFMPEG_ZIP= override. 135 MB of DLLs in git would tax every
commit on this 9p tree; the URL + hash are the audit trail LGPL §6 wants.
- ytLive.csproj copies ffmpeg\** to output and publish (Always), and a
GuardBundledFfmpeg target fails the BUILD if the folder is missing, so a
fresh clone finds out before a take rather than during one.
- FfmpegLocator loses the downloader, the zip extraction and the
%APPDATA%\ytLlive\tools cache. Order is now bundle -> PATH, deliberately
inverted: a PATH ffmpeg may be a different major version or a GPL build,
and the bundle is what was pinned, license-vetted and tested. A missing
bundle throws loudly; the old "found something on disk" path could satisfy
a missing bundle with a stale copy, and silent drift is the worst failure
mode for a dependency certification inspects.
- ffplay.exe (18 MB) is not shipped; nothing calls it.
- THIRD-PARTY-NOTICES.txt: "downloads" -> "bundled" throughout, and the stale
build tag autobuild-2026-08-09-13-03 — the tag that 404'd — corrected to
autobuild-2026-08-31-13-27 with the exact artifact name and archive hash.
OpenH264 made precise: compiled INTO avcodec-63.dll, no separate binary.
Checked whether other third-party binaries needed bundling: no. e_sqlite3.dll
and WebView2Loader.dll already ship via NuGet into runtimes\win-x64\native\,
OpenH264 is inside avcodec-63.dll, the rest are managed. Two gaps remain that
bundling cannot fix, recorded in the map: the WebView2 Evergreen runtime is a
machine prerequisite (TASK 48 item 2), and Velopack's updater downloads and
executes, so its teardown is a compliance action.
Tests: 16 locator facts, suite 379/379, 0 warnings. The integration test runs
the bundled ffmpeg -version, which is the only assertion that proves the
sibling libav*.dll resolved — presence checks pass with the DLLs missing and a
shared build then fails to start. TheLocatorCarriesNoNetworkCapability keeps
10.2.2 from rotting back.
Analysis: TASKS/research-store-certification.md §4.
Reported 2026-09-27: click avatar -> Change Account -> cancel in the Google
chooser -> back to a signed-out app, then "cannot sign-in because the callback
url was not released".
Two independent defects:
1. ChangeAccountAsync ran `await SignOutYouTubeAsync(); await SignInAsync();`.
SignOutYouTubeAsync -> TokenStore.Clear() -> deletes ytLlive.auth, so the
working account's token was destroyed before the browser even opened. It is
now just `await SignInAsync()`: success overwrites the token via the
sessionChanged hook, cancel/failure keeps the current session. The explicit
sign-out was never needed.
2. Abandoning the browser gives the app no signal, so the OAuth attempt held
localhost:8765 for its full 5-minute timeout and a retry could not bind. A
new AuthenticateAsync now cancels and awaits the abandoned attempt first.
That takeover is serialised by a SemaphoreSlim: the first version cleared
the in-flight marker before awaiting, so a caller arriving in that window saw
a free port and raced to bind it -- reproducing the very failure it was
written to prevent. My own test caught that; reasoning had "proved" it fine.
Also adds an `openBrowser` ctor seam so tests never shell out to a real
browser, and corrects the ai.md line that documented "Logout / Change Account ->
SignOutYouTubeAsync" as intended behaviour.
Test: YouTubeAuthServiceTests.RetryingAfterAnAbandonedAttempt_ReleasesTheCallbackPort
Full suite 370/370, 0 warnings. Coverage gap noted in HANDOFF.md: the ordering
fix has no automated test because _youtubeAuth is hardcoded in MainViewModel
and ChangeAccountAsync is private.
The reported cross-instance effect is NOT this cause and stays open -- no code
path can sign out a second instance (per-instance TokenStore, local delete, no
server-side revoke).