# Windows locked/display-off native screenshot proof

PASS on DESKTOP-23BSROR, Windows 11 build 26200, Electron 44.4.2. Source remained clean at final `060e476a8008b69c937082ce2c415d5dc7568837`, compared with exact base `26285ab80513260d1ff29d2c3fbe18f21990cb62`. The matched batch ran from 2026-10-08 10:22:23.667 UTC to 10:23:09.777 UTC.

Base produced four native PNGs, two fresh shown-window captures, two stale minimized-window captures and two hidden-window native capture failures after bounded retries. Final produced six of six fresh PNGs across the same shown, minimized and hidden controls in 58–88 ms. The six distinct changing pixel markers were 7919, 15838, 23757, 31676, 39595 and 47514. All ten saved PNGs were independently decoded again after native teardown, with agreeing results and SHA-256 hashes in `independent-saved-png-verification.json`.

Both original guests were prepared while unlocked/display-on before the parent-coordinated human transition. Base Electron PID 50856 and final PID 16816 each retained guest 2 in its separate native process and fresh profile. Both recorded lock-screen at 10:20:50 UTC. Display notifications recorded off at 10:21:51.252 UTC. Every request had WTS locked, independently corroborating same-session LogonUI, and display0 before and after capture. All 90 passive WTS/root observations during the batch also agreed. The input-desktop reader still returned Default, so its value alone is not used to establish lock. No display-on notification or unlock was observed during capture. Each request preserved the original guest and restored prior host and guest throttling.

The retained exact base build was byte-identical to its prior manifest. The final proof host was rebuilt only to use a separate control listener at 19794, allowing both original native guests to remain live through the same human transition. The fixture remained at fixed port 5753. Production preload, IPC, Manager, capture and rendering implementations were unchanged. Both build source maps matched all 123 production project-source entries against actual source bytes and pinned Git source. The final Manager working file uses CRLF while its Git blob uses LF, recorded explicitly in `windows-build-integrity.json`. The immutable prior proof was preserved.

T3 preview status reported unavailable and preview_open failed on the connected Windows client. It cannot target these proof-only native runtimes. This authorized driver invoked the real production preload → Electron IPC → production schema/handler → Manager → native capturePage → production PNG artifact. It did not substitute a capture or change rendering. Current server-browser automation uses a separate CDP path; this proof makes no claim about that path or full React/broker/MCP traversal, recording coexistence, provider behavior or mobile. Mac proof was not repeated. Sampled OS qualification cannot exclude an unsampled lock transition or missed notification, and this small batch is not a general performance bound.

The durable READY receipt expired at 10:35:04 UTC but coordination and testing completed before expiry. Parent forwarded confirmation at 10:22:07 UTC; host receipt at 10:22:19.703 UTC gives 12.703 seconds apparent delay. Both use this Windows environment, but no independent clock synchronization measurement was made, and the apparent delay includes transport and scheduling. Human confirmation was not used in place of observed state. No agent/helper OS power, display, lock, unlock, assertion, policy or scheduled action was performed.

Both native guests/windows and their process trees were closed normally; captured launcher PIDs 59844/54080 and passive observer PIDs 41680/66072 were stopped or exited. All 14 captured owned PIDs were absent afterward. Fixture/control ports 5753, 19793 and 19794 had no listeners. Thread preview tabs were empty; no owned streams, mappings or scheduled jobs were created. Exact lease `preview-background-screenshots-desktop-windows-20261008T101809Z-4b019d13` was released at 10:23:30 UTC and its holder/request were absent from the final ledger. Cold builds, isolated profiles, artifacts and immutable proof remain inventoried in `final-manifest.json`. No source edit, commit, push, PR, integration, rebase, new review or repeat of previous passing tests occurred.