Root cause

frontend/packages/ui/src/resource-page-common.tsx: header shows directoryItems when homeNavigationItemsis empty.

frontend/apps/desktop/src/components/edit-nav-header-pane.tsx: popover seeds docNav only from homeDocument.detachedBlocks.navigation.

So sites using header fallback (no explicit navigation detached block) render nav links in header, but editor menu sees [] and shows only “Add Navigation Item”.

Plan

frontend/apps/desktop/src/components/edit-nav-header-pane.tsx

import useDirectory, getSiteNavDirectory, packHmId, nanoid, useMemo, useRef.

keep current explicit-nav extraction as-is.

add directory query for homeId.

build fallbackNav: HMNavigationItem[] from getSiteNavDirectory({id: homeId, directory}).

text: item.metadata.name || ''

link: item.id ? packHmId(item.id) : item.webUrl || ''

type: 'Link'

id: stable synthetic block id per item key via useRef(new Map()); generate once with nanoid(). Important so drag/reorder/edit state stays stable across renders.

choose source:

machineNavigation first

else explicit publishedNav if non-empty

else fallbackNav

pass that into EditNavPopover.

Tests: add frontend/apps/desktop/src/components/__tests__/edit-nav-header-pane.test.tsx

mock EditNavPopover; assert received docNav.

cases:

no explicit nav + directory items => popover gets fallback items.

explicit nav exists => explicit nav wins over directory fallback.

machine draft nav exists => machine nav wins over both.

Optional small cleanup

extract tiny local mapper(s) inside edit-nav-header-pane.tsx for readability only if needed; no new shared module unless duplication grows.

Why this fix

minimal; desktop-only.

matches what user currently sees in header.

preserves existing publish flow: first edit on fallback nav creates explicit navigation block, which is the expected transition from auto-nav to custom-nav.

Unresolved questions

Should editor fallback mirror only the public header (getSiteNavDirectory default), or should it include editor-visible private children too? My read: mirror public header exactly.