# MyMistakes.md > 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.