The headline feature is air-gapped BYOK: you can now point VS Code at Ollama or any compatible local model without GitHub authentication, which matters for restricted corporate or offline environments where the current cloud-gated flow was a hard blocker. The custom endpoint provider, previously experimental, graduates to stable in this release — so self-hosted and enterprise AI backends get a supported path forward. The browser device emulation is a quieter win: responsive design testing (device sizes, touch emulation, user agent switching) now lives inside the editor rather than a round-trip to Chrome DevTools. The preview Agents Window adds session hover details and an experimental local harness, and local agent sessions now emit standardized OpenTelemetry attributes under `github.copilot.*` — useful if you are already running observability pipelines and want AI coding sessions to show up alongside the rest of your traces.