# Proof audit pass 2

Target: [#22385](https://git.cafe/pingdotgg/t3code/pulls/22385), [#22385](https://github.com/pingdotgg/t3code/pull/22385). Contributor branch FllipEis:philipp/fix-lineage-scrollbar-shift; original remote head [1ff2c383](https://git.cafe/pingdotgg/t3code/commit/1ff2c383984bf2e4a1e40a0fb556c042acf82469).

Reviewed local AFTER [c652da37](https://git.cafe/pingdotgg/t3code/commit/c652da37518db84baa6025b3347cd2158ef5e916) against origin/main; independently confirmed merge-base BEFORE [67c0fc0c](https://git.cafe/pingdotgg/t3code/commit/67c0fc0cdaf963b103518862dd7b68a9c758ecf2). Read-only source inspection exclusively in /home/ubuntu/wt/pr-22385. Completed within 15-minute budget. No browser, server, capture, fixture replay, test run, source edit, fetch/reset/checkout, forge comment, push, merge, PR body edit, ops or ledger change.

## Findings

1. Evidence gate remains pending: 0/20 required before/after pairs, no flow captures, no two-threshold diff images, and no delivered executable seed/fixture. Therefore image SHAs, viewport/theme coverage, visible changes, clipping, partial-row hint and interaction claims cannot be verified. There is no delivered capture to rebuild or compare; replay was also expressly prohibited for this audit. Pixel delta is unavailable, not zero.
2. The reported blocker is sound for the configured browser runtime. The documented probe overflows (600px content / 100px client height) while offsetWidth and clientWidth remain 200px, including with explicit 6px scrollbar styling. Stable gutter then reduces clientWidth to 194px. These results cannot establish baseline auto-overflow narrowing. They are configuration diagnostics, not lineage screenshots. I reviewed their consistency; I did not independently rerun the probe.
3. Source confirms ServerBrowserContexts.ts launches headless with ignoreDefaultArgs containing only --enable-automation. Playwright's headless --hide-scrollbars default is a plausible explanation, not independently verified as an effective process argument here. No supported launch-argument control has been established for preview_open. The limitation is this configured runtime and required classic-scrollbar reproduction, not inherent inability to verify the web surface. No runtime modification or alternate automation is proposed or attempted in this audit.

Implementation verdict: no defect found in the full local origin/main...HEAD diff. Only ThreadRelationshipsControl.tsx changes: stable-gutter utility plus explanatory comment. Original 13.5rem and expanded min(28rem,55dvh) caps remain intact; the conditional 12rem/14rem tradeoff is absent from this head. Reserving a lane before overflow is an expected short-list width/truncation change and remains visually unverified. Previously reported tests are contextual, not independently rerun proof. Web only applies; no desktop requirement.

## Matrix coverage

Every row requires both 1440×900 and 390×844, light and dark, with BEFORE and AFTER images per combination. Zero pairs or diff images delivered for every row.

| Row | Required state | Pairs delivered/required | Audit status |
|---|---|---:|---|
| F1 | Short mixed lineage, all three groups | 0/4 | Missing; reserved-lane/truncation and control visibility unverified |
| F2a | Six visible of twenty | 0/4 | Missing; pre-overflow geometry unverified |
| F2b | Eighteen visible and overflowing; exhaustion/bottom supplements | 0/4 | Missing; width stability, hint, final-row access unverified |
| F3a | Workflow collapsed | 0/4 | Missing; initial geometry unverified |
| F3b | Workflow expanded and overflowing; phase/scroll/collapse supplements | 0/4 | Missing; expanded cap, clipping and flow unverified |

No claim of visual approval, nothing-else-changed, or merge readiness is supported. Resume the original matrix only after an authorized browser runtime configuration demonstrates nonzero auto-overflow gutter consumption. This is a pending evidence gate, not an implementation rejection.

Inputs: [pass 1 matrix](https://gh-file-drop-api-prod-mi5fy3sowv63ufte.pinglabs.workers.dev/f/b26cf39ccd661d9a/pr-22385-proof-pass1.md), [capture blocker](https://gh-file-drop-api-prod-mi5fy3sowv63ufte.pinglabs.workers.dev/f/324869dc39713f22/pr-22385-capture-blocker.md). Local copies read in /tmp. PR registered with the current thread and registration checked.

VERDICT: INSUFFICIENT F1, F2a, F2b, F3a, F3b