[teamleaderleo]

A cmux NEXT NIGHTLY can enter Sparkle's silent-install path when an older SUAutomaticallyUpdate preference remains set. Sparkle then owns the staged installer and stops the normal replaceable background-check path, so a restart can install the stale item while newer nightlies wait. This PR makes background mode own the staged reply by disabling that legacy silent-install preference when the updater is configured, preserving the scheduled check cadence and allowing the staged item to be replaced by the newest feed result.

The regression test seeds the persisted automatic-download preference, enables background mode, and verifies the silent path is disabled. Existing background-install tests continue to cover staged install and prompt behavior.

Validation:

• git diff --check
• Fleet package test: cmux-ci run --class isolated --script scripts/ci/run-swift-testing-suites.sh --ref <head> --arg Packages/macOS/CmuxUpdater (huge-blue client is not authorized for the fleet controller; the PR's routed CI covers the same package)
• Independent Codex correctness-first review: SHIP at 437e98b789be39ab3b25be5642eb658d51bfbffd

Closes the NIGHTLY symptom where SULastCheckTime stopped after staging and idle install never fired.

Agent session: huge-blue

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review 437e98b: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr25129 -f ref=updater-staged-schedule-recovery-next -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); no finished base run on e01ff7d to compare; do not merge until green; see lane-rules

[teamleaderleo]

Bead cx-em8km created for this PR by the cmux coordinator.

[teamleaderleo]

Review (subagent, correctness first): SHIP at 437e98b

The access-control blocker is fixed: the private defaults store remains in UpdateController.swift and the extension calls a narrow internal mutation seam. Behavior review confirms background mode is configured before updater start, scheduled checks remain enabled, and the app-owned staged installer remains replaceable. Diff checks pass; native package execution is delegated to the fleet/CI path.

[blacksmith-sh]

Found 9 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmp3w90iah7/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmpt21_j_t1/summary-missing.json (live):/summary-missing.json (live):	View Logs
[new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows/ [new_workspaces] debug.new_workspace timed 0 of 50 new workspace rows	View Logs
[new_workspaces] the window draws no frames/[new_workspaces] the window draws no frames	View Logs
[tabs] debug.tab_switch timed 0 of 40 switches/ [tabs] debug.tab_switch timed 0 of 40 switches	View Logs
[tabs] the window draws no frames/[tabs] the window draws no frames	View Logs
bench OTHER_SWIFT_FLAGS is 'OTHER_SWIFT_FLAGS=$(inherited) -DCMUX_BENCH_HOOKS -DCMUX_BL OCKING_CHECKS'/ bench OTHER_SWIFT_FLAGS is 'OTHER_SWIFT_FLAGS=$(inherited) -DCMUX_BENCH_HOOKS -DCMUX_BL OCKING_CHECKS'	View Logs
bench OTHER_SWIFT_FLAGS is 'OTHER_SWIFT_FLAGS=$(inherited) -DCMUX_BENCH_HOOKS -DCMUX_BL OCKING_CHECKS'/ bench OTHER_SWIFT_FLAGS is 'OTHER_SWIFT_FLAGS=$(inherited) -DCMUX_BENCH_HOOKS -DCMUX_BL OCKING_CHECKS'	View Logs
convention violations found (ERROR lines above)./ convention violations found (ERROR lines above).	View Logs

^{Need help on this PR? Tag @codesmith-bot with what you need.}

[github-actions]

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4023940374302 (8542c30217)