The zoom buttons render an icon through a slot and carried only `title`, so their
accessible name was empty: a screen reader announced "button" with no indication of what
it does. title is a tooltip, not an accessible name — unreliably announced, and never
surfaced to touch users.
Found while proving the research-dashboard zoom controls actually work. They do: a click
triggered six tile requests at zoom level 2, so the open-work item is function-verified,
not just present. The probe that matched aria-label found nothing while the probe that
fell back to title found both buttons, and that discrepancy was the defect.
One binding in the shared MapControlButton reaches all eight control buttons — zoom in
and out, fullscreen, location, help, share, hamburger, theme — across seven map bundles,
because every one composes this base. No caller changes: the component does not set
inheritAttrs:false, so a caller passing its own aria-label still wins through normal
fallthrough, and undefined omits the attribute when there is no title to mirror.
Verified across all seven bundles: 34 control buttons, 0 without an accessible name.
Standalone repo that builds embeddable JAMstack map bundles (web components),
composes them into a lazy-loaded SPA via layouts/, and optionally wraps a
Capacitor Android/iOS app — one build, choose your output/CDN. Diátaxis docs.
History reset to a single clean commit; no PII, IPs, or internal terms.
