Two seams, in the shape docs/extension-points-architecture.md settles on:
a Laravel event with a mutable payload, dispatched unconditionally, and
with nothing listening the documented default holds. A community
installation gets an empty list and a null callout, which is exactly what
it had before.
ResolvingNavigationLinks exists because the sidebar is a hardcoded array
in app-sidebar.tsx, so a package could not contribute to it at all — the
nav entry was a separate manual edit every time a package grew a screen,
and being manual it was forgotten more than once. Staff-only, decided in
HandleInertiaRequests rather than trusted to each listener: these render
in the administration area, and a client's portal shows their own files
and nothing about the installation. There is a test that a listener adding
unconditionally still reaches no client.
ResolvingDashboardCallout is one band above the widget grid rather than a
widget in it. The grid is a closed list of keys that dashboard.tsx renders
one by one and each viewer arranges, so a message that mattered would sit
wherever somebody dragged it, or under a fold, or switched off. One at a
time, first listener wins: a dashboard that can accumulate banners
accumulates them, and the second is what teaches people to skip the first.
Core learns nothing about what either seam carries. Titles, URLs and copy
all arrive from the listener, and that is not fastidiousness — the first
caller is the hosted edition's link to its own customer portal and its
pitch to free instances, which is commercial copy belonging to one
offering and has no business sitting in the public repository because the
sidebar happens to live here.
An external link renders as a plain anchor opening in a new tab, never an
Inertia <Link>: Link expects a page component back and another origin will
not give it one, so it fails without saying so. It is also never marked
active — nothing outside this app is the page you are on.