Cross-lane automatic updater verification — 2026-07-22/23

Result

Desktop Material's installed legacy Super Express build 3.6.3-beta3-s000000000201 now moves forward through the ordinary and Super Express release lanes. Both lanes use a fixed-width alphabetic z version that sorts above the historical b… and s… packages and avoids the installed Squirrel/NuGet comparer's 32-bit numeric prerelease overflow.

This legacy s…→z… frame and its hash are reserved historical evidence. They address the immutable blob at 923dbb51acad8f01f01f1c100c6945c7a2e08e23; a current-source updater acceptance must use a distinct capture target rather than overwrite or relabel this basename.

Fail-closed correction

Commit 241cc90ce90f240bad075edac7ebe43eea515df8 first unified the release lanes. Its CI run 29976419466 exposed an OverflowException when the legacy NuGet comparer parsed an 11-digit decimal prerelease tail. Packaged E2E failed and the release workflow created no Release.

Commit 04246fdf12c09446b88d2f40130581d603131c8e replaced that tail with a nine-letter base-26 run-ID encoding. Local acceptance included the installed Squirrel comparer, 1,000 adjacent versions, carry boundaries, ReleaseEntry parsing, 16 focused updater/workflow checks, all 31 script checks, TypeScript, targeted lint/format, and diff integrity.

Remote publication

Exact-source CI 29977738533 passed Windows x64, Windows arm64, installed packaged E2E, unit/script tests, and lint for 04246fdf12c09446b88d2f40130581d603131c8e. Code scanning and Pages also passed. Downstream Build Installers 29978844761 published and promoted exact-target Release v3.6.3-beta3-zadtberjmv with all six required assets. Its RELEASES entry was:

4D59C42287F7A76818F05CF4BFD55B3CE8E6B9EE GitHubDesktop-3.6.3-beta3-zadtberjmv-full.nupkg 311110425

The live automatic update installed that version before the isolated onboarding reload could preserve the transient ready event. To capture the real UI without rewriting installed package state, an intentional same-source Super Express run 29980281736 ran the full unit/script gates, built and verified the payload, and published greater Release v3.6.3-beta3-zadtbhvdfc. GitHub's Latest endpoint resolved to that exact non-draft, non-prerelease Release on 04246fdf12c09446b88d2f40130581d603131c8e.

Its feed entry was:

60AF9476C5D4ADEAF3CA2AE316CBFBDC307A2B92 GitHubDesktop-3.6.3-beta3-zadtbhvdfc-full.nupkg 311110476

Installed Squirrel evidence

The ordinary background check began from the exact legacy executable. The sanitized appended log segment recorded:

• localVersion=3.6.3-beta3-s000000000201;
• download of GitHubDesktop-3.6.3-beta3-zadtberjmv-full.nupkg;
• writing app-3.6.3-beta3-zadtberjmv and repointing the execution stub;
• Finished Squirrel Updater; and
• a later check using localVersion=3.6.3-beta3-zadtberjmv.

For the second UI-visible check, the manual request included skipGuidCheck=1, compared from zadtberjmv, downloaded the zadtbhvdfc full package, wrote its app directory, repointed the stub, and finished. Staging identifiers and query GUIDs were redacted and are not stored in this repository.

Off-screen UI acceptance

The fixed Lowlevel MCP service ran from checkout ed1427f69b20dcd66df1de2ae3c6ba6591e2e640 at http://127.0.0.1:8765/mcp. The scheduled task used its fixed venv Python, checkout, loopback host, and port. One uniquely named off-screen Win32 desktop launched only the exact installed legacy executable with an isolated profile and disposable Git fixture. No visible-desktop switch occurred.

After Help → About Desktop Material, the test reproduced You have the latest version on the running s000000000201 UI. Once the higher Release was Latest, the HWND-targeted Check for Updates action showed Downloading update… and the top-edge progress indicator. It then showed An update has been downloaded and is ready to be installed plus Quit and Install Update. The install button was deliberately not clicked.

The accepted client-only capture is the immutable auto-updater-update-ready.png blob at 923dbb51acad8f01f01f1c100c6945c7a2e08e23: 960×660, 49,195 bytes, SHA-256 a02cffa612114be3af5e0fffcd5b602a4ba4dfd3226298e48d143a6bed76bd4d. Two independent nonblank captures were byte-identical. The dialog was closed, File → Exit ended the saved app PID, no owned helper remained, the desktop had zero windows, and the off-screen desktop closed successfully.