Sidebar collapse does not survive reload — sidebar_state cookie is written but never read back (SidebarProvider always starts from defaultOpen = true) #4234

Symptom

Collapsing the console sidebar does not survive a page reload.

• The cookie is written: sidebar_state=false, 7-day max-age — and it is still present after the reload.
• Yet the sidebar renders expanded: width 255px, data-state=expanded.
• Measured at +2s / +4s / +8s after load specifically to exclude a settling race — expanded at every sample.
• Reproduced 3×.
• Expected: with sidebar_state=false present, the sidebar renders collapsed on first paint.

Root cause

packages/components/src/ui/sidebar.tsx only ever writes the cookie and never reads it back.

• SIDEBAR_COOKIE_NAME = "sidebar_state", SIDEBAR_COOKIE_MAX_AGE = 60 * 60 * 24 * 7 (~lines 36-37) — matching the observed 7-day max-age.
• setOpen writes it on every toggle: document.cookie = ... (~line 101). That is the only occurrence of the cookie name in the whole package.
• SidebarProvider initialises from the prop default: defaultOpen = true → const [_open, _setOpen] = React.useState(defaultOpen). There is no cookie read, no lazy initialiser, no hydration effect.
• No SPA caller passes a cookie-derived defaultOpen. The only defaultOpen={false} call sites on main are marketing/demo components in apps/site; the console shell passes nothing, so it gets true every load.

The upstream shadcn original resolves this by reading the cookie in a server component and handing the value down as defaultOpen. A pure SPA has no equivalent of that step — so the fix needs an SPA-side read (a lazy useState initialiser or equivalent that parses document.cookie on mount), not merely "pass the prop". Passing a prop from the console shell alone still leaves every other SPA consumer broken.

Verified still present on objectui origin/main @ bb68488 (current at filing time), not just on the vendored console 09987b68 the run used.

Honest contrast — the rest of shell-nav-personalization is healthy

This is a narrow defect, not a broken persistence layer:

• Pins, favorites and recents all persist correctly, backed by real sys_user_preference rows.
• Reorder is blocked — not failing, untestable: no drag affordance is rendered at all.
• Recents capture record visits but not object-list visits.

Reproduction

Framework a86db175, vendored console 09987b68, showcase app, authenticated session.

1. Collapse the sidebar.
2. Confirm the cookie: sidebar_state=false, max-age 7 days.
3. Reload the page.
4. Confirm the cookie is still sidebar_state=false.
5. Measure the sidebar at +2s, +4s and +8s after load.

Observed: 255px and data-state=expanded at all three sample points. Reproduced 3×.

Dedup

Searched objectstack-ai/objectui for sidebar_state, SidebarProvider, defaultOpen, and sidebar-collapse-not-persisted symptoms — no open or closed duplicate found.

Source

Extracted from the QA run objectstack-ai/objectstack#7514 (framework a86db175, vendored console 09987b6). Root-cause re-verification is against objectui origin/main @ bb68488.