OpenElement treats third-party Custom Elements as standards-based dependencies. Current builds use explicit package-island configuration and available Custom Elements Manifest metadata for SSR admission.
@openelement/element owns authoring; app and adapter-vite keep application and build behavior separate.
Known packages can be configured as package islands and use available CEM metadata without importing retired package surfaces.
Universal DSD/light/client-only classification and hydration-mismatch diagnostics are `0.43` roadmap work, not a current market claim.