The v1.65 migration suite relied on the host being macOS — on the
ubicloud runner the script's uname gate early-exited every test with
empty output; a Darwin uname shim in the shared setup runs the real
path everywhere (the non-Darwin test still overrides it with Linux).
The 1ms-budget brain-context test assumed 1ms is always too short; the
runner's fake gbrain answered in 0ms and no SKIP printed — the fake now
sleeps 300ms so the timeout is a certainty, while --version stays
instant for the detection assertion.
The migration (renamed from the provisional v1.64.0.0 slot, which open
PR #2564 claims) deleted only the poisoned .app while Playwright's
INSTALLATION_COMPLETE marker survived in the revision dir — so the
advertised 'bunx playwright install chromium' re-fetch no-opped and the
user finished the upgrade with no browser and a success message. Now:
the whole chromium-<rev> dir goes, bunx runs cwd-pinned to the install
root, .done is gated on a verified executable, and a needs-refetch
sentinel makes re-runs retry a failed download. Stranded rev dirs
(markers without .app) also re-trigger. 6 hermetic tests, red-first.