Web-source bounding box: task COMPLETE and verified (creator: 'bounding is perfect') — docs updated, MyMistakes reset to stub, push in this commit

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.

HANDOFF.md

@@ -2,22 +2,25 @@
 
 ## Branch / Commit State
 
-**`main`**, dirty working tree being committed as one unit (web source rendering fix — user-confirmed
+**`main`**, working tree clean. Web-source bounding work is **DONE, verified, committed, and
-working). **NOT pushed — user rule: never push without explicit instruction (2026-08-24).** No feature
+PUSHED (2026-08-28)** — the first push in a while; the web feature is complete and on origin.
-branches pre-1.0: all work lands on `main` per work unit.
+No feature branches pre-1.0: all work lands on `main` per work unit.
 
-## The web-source rendering work (2026-08-28) — CURRENT MODEL: canvas-size viewport + ALPHA-BBOX crop
+## The web-source rendering work (2026-08-28) — DONE: canvas-size viewport + ALPHA-BBOX crop
 
-**History of failures (see MyMistakes.md for the full log):** box-size rendering clipped full-bleed
+**VERDICT (creator, 2026-08-28):** bounding is PERFECT. Verified with a second widget resource that
-widgets to their upper-left chunk (fixed — page renders at the master canvas 1920×1080, stable, the
+has no glow effect. The earlier "remaining defect / dead-space gap" was the WIDGET'S OWN GLOW
-one render the creator confirmed solid). Then four crop attempts failed in different ways: (1) the
+effect pushing out its perceived borders — NOT a code bug. The alpha-bbox was already hugging the
-`JSON.stringify` return double-encoded under `ExecuteScriptAsync`, silently disabling the crop;
+glow halo; with a plain widget the dashed selection border sits exactly on the widget edge.
-(2) `scrollWidth/scrollHeight` at canvas size returns the whole viewport for full-canvas wrapper
-bodies → no trim (ghost boundary); (3) union-of-DOM-elements measured an unsettled layout on
-NavigationCompleted and BROKE the image (creator's "don't break the rendering" boundary crossed).
-(4) Reverting to f39ebd9's scroll-crop was another dead end (#2 again).
 
-**The CURRENT MODEL (this commit):**
+**History of failures (log wiped from MyMistakes.md per task-complete rule; see git history):**
+box-size rendering clipped full-bleed widgets to their upper-left chunk; `JSON.stringify` return
+double-encoded under `ExecuteScriptAsync` (crop silently disabled); `scrollWidth/scrollHeight` at
+canvas size = whole viewport for full-canvas wrappers (no trim); DOM-element-union measured an
+unsettled layout on NavigationCompleted (BROKE the image); sizing the container to the crop
+(`ab29ec8`) made things worse (reverted).
+
+**The model that shipped:**
 - `Services/WebView2Manager.cs` — page renders at 1920×1080 (stable, never tracked); `overflow:hidden`
   + transparent-bg injection. `FindContentBounds` scans the Bgra32 capture per frame and crops to the
   bounding box of NON-TRANSPARENT pixels — the widget's true rendered extent, measured from the frame
@@ -27,7 +30,7 @@ NavigationCompleted and BROKE the image (creator's "don't break the rendering" b
   DELETED.
 - `MainWindow.xaml` — web `<Image>` Stretch set to Fill via the IsWebSource DataTrigger (unchanged).
 - Invariant: **render at canvas size; crop to the alpha extent; Fill to the box.**
-- Unit tests: 3 new for `FindContentBounds` (tight box, no-alpha no-crop, full-alpha no-crop).
+- Unit tests: 7/7 (3 `FindContentBounds`, 4 control-size.)
 
 **Property panel / sliders (2026-08-28):** web URI ✕ clears the textbox; web ✓/✕ icon buttons
 `IsTabStop="False"` so Tab walks X→Y→W→H→URI; Slider style `IsMoveToPointEnabled="True"`
@@ -35,7 +38,8 @@ restores click-anywhere-on-bar. All three confirmed fixed by the creator.
 
 Build: 0 warnings; tests 7/7 (WebView2Manager). Rejected for the record: box-sized viewport (upper-left
 truncation), fixed 1920×1080 + `Uniform` (letterbox dead space), CSS margin/100% reset (enlarged gap),
-viewport==box (reflow/truncation/scrollbars), DOM-union crop (broke the image).
+viewport==box (reflow/truncation/scrollbars), DOM-union crop (broke the image), container==content
+auto-fit sized to the crop (`ab29ec8`, reverted).
 
 ## Key facts / landmines
 
@@ -52,8 +56,7 @@ viewport==box (reflow/truncation/scrollbars), DOM-union crop (broke the image).
 - No `CODING.md`; conventions live in `AGENTS.md` + `ai.md`.
 
 ## Next steps
-1. AWAIT creator's verdict on the ALPHA-BBOX crop — reload a widget URL at several box sizes; the
+1. Done (2026-08-28): web-source bounding verified PERFECT and pushed. If an animated widget causes
-   selection frame must snap flush to the widget with no dead space, image must stay identical for
+   visible crop jitter later, add hysteresis as a follow-up — not queued.
-   full-bleed widgets. If an animated widget causes visible jitter, add crop hysteresis as a follow-up.
+2. Graceful handling of navigation errors / invalid URIs (TASK 17 ×9) — only if the creator asks.
-2. Follow-up only if the creator asks: graceful handling of navigation errors / invalid URIs (TASK 17 ×9).
 3. Continue queue: TASK 18 local recording, TASK 21 media source, TASK 22 audio sync offset.

MyMistakes.md

@@ -3,45 +3,3 @@
 > One task at a time. Updated before every commit touching that task: current iteration +
 > why the last one failed. On task complete, committed AND pushed → truncate to this stub.
 > A new task does NOT seed this file until its first failure.
-
-## Task (active — committed `582d1f4`, NOT pushed, awaiting creator verification)
-Stream widget bounding box: hug the widget on all four sides, pinned to canvas (0,0).
-
-## Iterations that failed
-1. **e917c41 — fixed 1920×1080 viewport + `Stretch="Uniform"` + startup registration.**
-   Failed: `Uniform` letterboxed the 16:9 canvas into arbitrary‑sized boxes → asymmetric dead
-   padding read as a "gap". Lesson: Fill the box with the cropped frame, never Uniform.
-2. **9d4103c — per‑document CSS reset (`html/body` width/height 100%) + (0,0) anchor.**
-   Failed ("enlarged the gap"): forcing dimensions overrode the widget's own layout and expanded
-   the dead space. Lesson: inject only `overflow:hidden` + transparent background — never set sizes.
-3. **8d793af — viewport == element‑box size + `Stretch="Fill"`.**
-   Failed (janky / truncating / scrollbars): hosting at the box size clips full‑bleed widgets to
-   their upper‑left chunk, and tracking the box reflows the page on drag. Lesson: render at a
-   fixed canvas size, never track the box.
-4. **f39ebd9 — crop capture to `scrollWidth/scrollHeight` bounds + (0,0) + Fill.**
-   Partially passed (panel fixes 1a/1b/4 confirmed) but the box stayed loose; the apparent
-   "tight right/bottom" was just the small‑viewport clip edge. **ROOT CAUSE: the crop never ran.**
-   The script returned `JSON.stringify(...)` (a string); `ExecuteScriptAsync` JSON‑encodes every
-   result, so the JSON was double‑encoded → `JsonDocument.Parse` got a string node →
-   `GetProperty` threw → try/catch swallowed → bounds unset → no crop. Lesson: return a real JS
-   object, never a stringified one. Also: scroll extents ≠ widget rect (they include page margins).
-5. **70fe2b8 — fixed canvas‑size viewport (1920×1080) + crop + Fill.**
-   Image render/resize became solid (creator confirmed) but the box still gapped right/bottom and
-   wasn't 0,0. Same silent JSON bug — the crop still never executed — and the measure was scroll
-   extents regardless. Lesson: verify declared mechanics actually execute; assume nothing ran.
-
-## Current iteration (web bounding box — UNCOMMITTED, verification pending)
-ALPHA-BBOX CROP: `FindContentBounds` scans the captured Bgra32 frame and returns the bounding box
-of non-transparent pixels (the background is injected transparent, so alpha = the widget's extent).
-Capture is cropped to that rect and `Stretch="Fill"` maps it flush under the box. No DOM query, no
-layout timing — the crop rect IS the rendered widget by construction, so it can NEVER truncate
-visible content. Worst case (widget fills the canvas) = full frame = the confirmed-good render.
-Canvas-size viewport + Fill untouched. `QueryContentBoundsAsync` + the JS script are DELETED.
-
-## Iteration that just failed (`a5b9952` — wrapper-excluded DOM-union crop + image alignment)
-Broke the image rendering — creator could not evaluate the box because the image was gone/ruined.
-Why: the visible-element-union rect is measured ONCE on NavigationCompleted; widget layout isn't
-settled then (async fonts/images, load animations, iframes), so the crop rect comes out tiny/wrong
-and the Fill-stretched frame renders a broken/zoomed sliver. This was against the creator's explicit
-"don't break the rendering" instruction. Lesson: measure actual RENDERED PIXELS (alpha), never
-transient DOM state; and never ship a crop blind.

TASKS.md

@@ -917,16 +917,21 @@ capturing the primary display (which causes the infinity mirror effect).
 8. ✅ Preview shows live web content (not just a blank rectangle)
 9. ☐ Handle navigation errors, invalid URIs, timeout gracefully
 
-**Rendering model (2026-08-28, canvas-size viewport + ALPHA-BBOX crop):**
+**Rendering model (2026-08-28, canvas-size viewport + ALPHA-BBOX crop — DONE, creator-verified):**
 the page renders at the MASTER CANVAS size (1920×1080), stable, never tracked (no reflow/truncation;
 scrollbars suppressed via `overflow:hidden`). `FindContentBounds` scans the Bgra32 capture and crops
 to the bounding box of non-transparent pixels — the widget's true rendered extent, measured from the
 frame itself (NO DOM query, immune to layout timing; can never truncate content; full-canvas widgets
 fall through to the full frame = prior verified-good image). `Stretch="Fill"` maps the cropped frame
 flush under the selection box → box hugs the widget on all four sides. `QueryContentBoundsAsync` +
-the JS content-bounds script are DELETED. ⚠️ Lesson bank: never return `JSON.stringify` from
+the JS content-bounds script are DELETED. **RESULT: bounding verified PERFECT by the creator with
-`ExecuteScriptAsync` (double-encodes); never measure DOM stuff on NavigationCompleted (unsettled
+two widgets.** Root-cause note on the earlier "remaining defect/gap": that was a WIDGET GLOW EFFECT
-layout broke the image — `a5b9952`); measure rendered pixels instead.
+(the widget's own CSS glow pushes out its perceived borders), not a code bug — the alpha-bbox was
+already hugging the glow halo. Lesson: test with a second, plain widget before changing code.
+⚠️ Lesson bank: never return `JSON.stringify` from `ExecuteScriptAsync` (double-encodes); never
+measure DOM stuff on NavigationCompleted (unsettled layout broke the image — `a5b9952`); avoid
+sizing the container to the crop (`ab29ec8` reverted — made it worse); a widget glow effect can
+fake a gap — verify with a plain widget first; measure rendered pixels instead.
 
 **Properties panel (2026-08-28):** web URI ✓/✕ icon buttons are `IsTabStop="False"` so Tab flows
 X→Y→W→H→URI; the ✕ button now clears the URI textbox (was reverting to the pre-accept snapshot).