Every reference to the Driver in library/ is reworded: the engineering reason
stays, the speaker and the quote go, and a decision still open reads
"provisional, pending a product decision". Comments only: each changed file
is identical after stripping comments (JavaScript, template and CSS, including
CSS comments inside the style strings shadow-DOM components inject).
Those style-string comments do ship, so several bundles change by exactly
those comment bytes.
"the element gets the tk to the element itself and does not need to only
gatekeep that to one component only — all components in a plugin can share
that tk" (Driver, 2026-09-23).
Inside ONE element that was already true: ProfileLoader provides
'mapboxToken' and eleven components inject it. The gate is the ELEMENT
BOUNDARY — every custom element mounts its own app with its own
ProfileLoader, which re-derives the token from its own profile-config, so a
composite that nests a real map hands the child nothing.
THE EXISTING FALLBACK COULD NOT FIRE. The ladder already read
window.MAP_TOKEN. MEASURED: that global IS set on the composite leaf and
the child still had no search bar — because the ladder lives in a
computed() and window.MAP_TOKEN is a plain global, not a reactive source.
The composite leaf FETCHES its token, so the computed resolved '' first,
cached, and never re-ran. useSharedMapToken makes it a ref that updates on
publish, and assignments to window.MAP_TOKEN are adopted through an
accessor, so already-generated pages keep working untouched. Storage lives
on window and changes travel as an event: each bundle is its own IIFE, so a
module-level ref is NOT shared between a composite and the bundle it nests.
THAT WAS NECESSARY AND NOT SUFFICIENT, which only measuring showed. With
the token shared and reactive the bar was STILL absent. Real cause:
GeocoderComponent's onMounted hit `typeof MapboxGeocoder === 'undefined'`
and RETURNED SILENTLY — no throw, no console error, no DOM. MapboxGeocoder
is "preloaded via index.html", true for a LEAF and false for a COMPOSITE
leaf, which generate-tree classifies as token-free while it goes on to nest
a real map. Measured, mapbox-gl-geocoder references per page: research-map
leaf 2, research-map-plus-grid leaf 0.
So the script is now fetched on demand when a host did not preload it,
reusing the exact shape the maplibre path already had (one loader, two
callers) and pinned to the same v5.0.0 the leaves preload. It resolves on
error as well as load, so a blocked CDN leaves the map usable and the bar
absent rather than hanging. This fixes every already-generated page without
regenerating any of them.
MEASURED on the built tree:
leaf mapbox search@56 legend@104
leaf maplibre search@NONE legend@58 (unchanged: maplibre stays bar-free)
composite search@56 legend@104 (was NONE)
library/ reaches every bundle, so all 22 rebuilt: 22/22, 7/7 pre, 18/18
post, and a browser sweep of five StackLayout consumers plus all seven
studio dashboards.