When the Socials button moved to the preview row, its 220px first column
was removed from the footer grid. The mic meter StackPanel still referenced
Grid.Column=1 which no longer exists — moved to Grid.Column=0. Build 0w.
Encoder dual-output: StreamEnabled/RecordEnabled/RecordPath options; per-output
ffmpeg block (stream ->flv, record ->mp4); throw unless at least one output.
RecordingFile: auto-name ty-<yyyymmdd>-<start hhmm>-0000.mp4, rename-on-stop to
ty-...-<len hhmmss>.mp4 with numeric-suffix on collision. LayoutStore persists
record folder. MainViewModel: REC/ON-AIR pills, status light, single Start<->End
button (replaces Start/Stop variants), StopStream no longer signs out, explicit
session timer. About overlay widened. Sign In label + spacing before Start.
Tests: 244 passed / 246 (2 pre-existing: AudioPipeline gains-mute, RoundClip).
Build 0 warnings. Scope check clean.
Memory-map correction (derived-solution rule, 2026-08-29): image-shrink recipe was
never recorded when first done, so it was re-derived. Added Derived-solution/recipes
rule to AGENTS.md; MyMistakes.md now a permanent recipes registry (records the
verified WPF-imaging shrink recipe); schema.md rows MyMistakes as registry; ai.md
points to the rule. README hero image replaced: 3.2MB screenshot -> 1400x794 ->
188KB docs/ytLlive-preview.jpg (JPEG q82).
Project lesson cited (the 2026-08 web-box saga, 9 commits): browser sources are fixed canvases
per OBS convention — the 'gap' was a widget CSS glow, not a bug.
Root-cause note: the apparent remaining gap was a WIDGET GLOW EFFECT (the widget's own CSS glow pushed
out its perceived borders), not a code bug — the alpha-bbox already hugged the glow halo. Verified
perfect with a second widget without the effect.
- FindContentBounds already trimmed the bitmap; the grid/box still rendered at the uncropped user
size, so Fill stretched the tight widget into a bigger frame = dead-between-content-and-border.
- ContentCanvasSize maps the crop rect to canvas units (1920/pixW per axis, DPI-correct) and the
preview event now carries (bitmap, canvasW, canvasH).
- OnWebView2PreviewBitmapChanged sets the element Width/Height to that size; the grid and the
SelectionOverlay (both bound to the element's Width/Height) now equal the widget exactly.
- IsPreviewDragging (set in MainWindow drag/resize) suppresses auto-fit mid-gesture.
- Tests 10/10 (alpha bounds, canvas-size mapping incl. DPI, control size); 0 warnings.
- FindContentBounds scans the Bgra32 capture for the bounding box of non-transparent pixels
(background is injected transparent, so alpha = widget extent). Crop to that rect + Stretch=Fill
maps the widget flush under the selection box: full-canvas widgets fall through to the full frame
(identical to the confirmed-good image); floating widgets get tight-fitted with no dead space.
- Removes QueryContentBoundsAsync + the JS script entirely — the DOM-union attempt (a5b9952) broke
rendering by measuring an unsettled layout on NavigationCompleted; alpha measurement is immune.
- 3 new unit tests: tight box, no-alpha no-crop, full-alpha no-crop. 7/7 pass, 0 warnings.
The wrapper-excluded content-union crop measured an unsettled layout on NavigationCompleted
(async fonts/images, load animations) and produced a broken/zoomed sliver — the image was gone.
Restoring the exact confirmed-good pipeline; the bounding-box dead-space problem stays open and
will not be touched without explicit approval.
- scrollWidth/scrollHeight returns the whole 1920x1080 canvas for widgets whose body/background
spans it, so the crop kept massive transparent margins and the content floated in the Fill box.
- ContentBoundsScript now unions every visible element's getBoundingClientRect, excluding elements
that span >=98% of the viewport (bodies, full-canvas background layers); full-bleed widgets fall
back to the full rect. Crop taken AT the rect's top-left (l,t) — content pins to bitmap (0,0).
- Web Image explicitly Margin=0 + Left/Top alignment so the frame and widget coincide at the origin.
- Canvas-size render untouched.
- ContentBoundsScript back to scrollWidth/scrollHeight extents, kept as a real JS object
(the JSON.stringify double-encode bug that silently disabled the crop stays fixed).
- Crop again from (0,0), no X/Y offset. The union-of-elements approach (582d1f4) created an
all-sides gap by including invisible full-canvas wrappers; revert to the proven code.
- QueryContentBoundsAsync now returns a real JS object (not JSON.stringify — ExecuteScriptAsync
double-encodes strings, which silently killed the old crop) and measures the union of every
visible body element's getBoundingClientRect: the widget's actual rect, top-left offset included.
- CaptureFrame crops AT that offset (x,y) instead of from (0,0), so the widget anchors at origin
and the box is flush on right/bottom. Fill maps the frame flush under the box.
Bundle exception (2026-08-27): this lands prior-session work plus today's
transparency fix as one commit per creator instruction.
WebView2Manager (new): off-screen WebView2 control parked at -5000/-5000 in
the window's visual tree, captures via CapturePreviewAsync every 100 ms into
a BGRA8 VideoFrame. Source Width/Height sync to the control via
PropertyChanged. JS transparent-background injection runs on every
NavigationStarting/NavigationCompleted so the page's own CSS does not paint
white over the capture.
Transparency fix: DefaultBackgroundColor = System.Drawing.Color.Transparent
set on the WPF control before EnsureCoreWebView2Async. The WPF SDK doc says
the value is forwarded to the controller on init; the IDL (ICoreWebView2-
Controller2) confirms alpha=0 makes the capture alpha-preserving. The
prior-session 'CoreWebView2.BackgroundColor' path was the wrong property
name and has been replaced.
LayoutStore: WebUri column added (idempotent ALTER TABLE) and round-tripped
on save/load (schema v11).
MainViewModel: WebView2Manager constructed on Loaded; loaded web sources
re-registered; Source.WebUri PropertyChanged forwards to manager.
MainWindow: off-screen host Canvas added to visual tree.
Tests: 3 scale-sync + WebView2_DefaultBackgroundColor_Is_Transparent +
LayoutStorePersistenceTests.WebSource_WebUri_Persists. 234/236 pass
(2 pre-existing failures unchanged).
Scale bug (DPI/physical-pixel mismatch) still open.