Snapshot checks pass; desktop acceptance remains incomplete

Review verdict

Recommend a GitHub comment reporting the passing checks and remaining limits. Do not treat this run as an unqualified approval of the full Windows desktop flow.

PR #15643 was open and ready for review. This is the complete PR diff, not an incremental stacked review. Base 4ee6bfd50ef4a089440d5c3662db2298da9cc50e; tested head af4cb6394dfa1f4b20ed12e4ba479eee4fdc84fe. Both were unchanged at the final check on October 4, 2026.

There are zero numbered defect findings. Previous discussions about navigation cleanup, transformed clips, and duplicate selectors were reviewed against the current implementation. The focused suite covers those corrections; this run independently checked duplicate selectors and clipping in a real renderer.

What the PR changes

The desktop collector reports current-view text, page and container scroll positions, and visible controls ahead of offscreen controls. The MCP formatter preserves current-view context when reducing its response size. Optional saveText captures loaded main-page text once, transfers it in bounded chunks to an environment-local UTF-8 file, and validates the document and URL around the pinned-tab snapshot. Failures remove the owned text artifact.

Sources: SnapshotPage.ts, Snapshot.ts, McpHttpServer.ts at the tested head.

The new contract fields are optional for older desktop hosts. This is a provider-independent MCP feature. Web and mobile are not alternate native capture hosts; remote/relay compatibility and the new text export were reviewed through contracts and focused server tests, not a multi-device acceptance run. Native OS screenshot capture is unchanged.

Verification results

Local commands and logs in this report's evidence links. Windows renderer cases: document scroll, nested scroll, duplicate selectors, hidden text, long loaded text, clipped overflow, visible controls ahead of the 200-control cap, empty page. Timings in raw results are single observations, not performance benchmarks.

The pinned commit also has passing GitHub snapshot jobs on Windows, Linux, and macOS, plus build, lint, and typecheck. These are CI evidence, not locally repeated Linux or packaged-app acceptance.

Supplemental screenshot from the Mac Browser panel. The fixture heading says Windows snapshot review, but this image is not Windows UI evidence. The separate native Windows checks validate DOM collection only.

Limits and setup failures

The global Vite+ CLI was 0.2.2; the checkout requires 1.0.0. Its early test run used a different Vitest and failed suite loading. Its formatter also reported a difference present in the base. Running the pinned local CLI resolved both. Neither is a PR finding.

vp i ultimately failed with ERR_PNPM_PATCH_FAILED on patches/uniwind@1.11.0.patch. That patch and dependency manifests are unchanged between base and head. The installed subset was sufficient for the successful focused tests, lint, format, and typechecks, but the full dependency setup remains incomplete.

The standalone renderer's screenshot experiment hit UnknownVizError; waiting for animation frames also stalled in this environment. The app already has unchanged capture retry logic. This is a fixture/environment limitation, not an established product regression. End-to-end image capture, the built app's actual saveText-to-file flow, and interactive Windows UI acceptance remain unverified.

No source files were changed. No fixes were pushed and no PR was merged. The report and a validation comment are published under the requested review workflow. The existing worktree is retained at E:\.t3\worktrees\t3code\t3code-75a8eb45.

Reproduce the checks

# From the pinned review checkout
node node_modules/vite-plus/bin/vp test run apps/desktop/src/preview/SnapshotPage.test.ts apps/desktop/src/preview/Manager.test.ts apps/server/src/mcp/McpHttpServer.test.ts apps/server/src/mcp/PreviewAutomationBroker.test.ts apps/server/src/preview/Snapshot.test.ts apps/server/src/mcp/toolkits/preview/tools.test.ts packages/contracts/src/previewAutomationSnapshot.test.ts packages/contracts/src/preview.test.ts

node node_modules/typescript/bin/tsc --noEmit -p apps/desktop/tsconfig.json
node node_modules/typescript/bin/tsc --noEmit -p apps/server/tsconfig.json
node node_modules/typescript/bin/tsc --noEmit -p packages/contracts/tsconfig.json

Native renderer fixture: native-renderer.cjs reads snapshot-expression.js from the same directory. Run it with an installed Electron executable and ELECTRON_RUN_AS_NODE unset. It creates isolated state beside the fixture and exits after the assertions.