Real desktop preview sharing reproduction

Run the same driver on each checkout after installing dependencies, downloading Electron, and building the desktop main process and bundled server. Requires headless-desktop (Xvfb + D-Bus + keyring), Node, Playwright Chromium headless shell, ffmpeg, and configured T3 browser sandbox support.

Start the checkout's web Vite server from apps/web with HOST=127.0.0.1 PORT=7611 T3CODE_PORT=15651 T3CODE_SINGLE_ORIGIN_DEV=1 vp dev.
Run: headless-desktop node prove-desktop.mjs <checkout> <output-directory> <before|after>
Optionally set CHROMIUM_EXECUTABLE. Keep these files together. Each run creates fresh isolated synthetic state. Nothing is copied from the installed app. The replay wrapper keeps the free replay turn active so the real thread-scoped preview MCP tools remain authorized; it does not replace browser capture.

The driver opens an actual Electron webview, pairs two independent Chromium client contexts, opens the existing native tab, starts/stops a real preview recording through MCP, then closes Viewer A's Browser panel and floating preview through the UI. It reopens A between the two cases to restore active streams on the base. Setup uses the app's right-panel store to select the existing tab and hide the details card. Captions identify each action. Native debugger instrumentation observes and forwards commands unchanged. Fixed observation windows record motion for human review; there are no pass/fail assertions on the bug.

Export: python3 render-evidence.py <run-directory>/result.json
This aligns the two client videos at their first caption and places A left, B right. No frames inside the reproduction are removed. Videos are the visual evidence; the transcript adds final-consumer lifecycle observations.

Raw output includes temporary credentials and local paths. Never publish raw logs or result.json.
