Release Notes

The Firebase SDK for Flutter (v4.20.0) is now available.

Firebase Apple SDK 12.19.0 introduces conformance for Swift 6 language mode, enabling use in Swift 6 strict concurrency contexts.

Firebase AI Logic now supports the stable gemini-3.8-flash model via the Gemini Developer API or Agent Platform Gemini API (formerly Vertex AI). The Developer API needs no Blaze plan, but legacy Vertex AI initialization must set location to global. Migration notes: MINIMAL thinking level fails with 400, thinking budgets are discouraged, several parameters (temperature, top-K, top-P, penalty and candidate count params) are removed or error, and prefilled model turns return 400.

Adds support for the FIREBASE_DEBUG_PATH environment variable and a --force flag to firebase ext:migrate, plus several unlisted fixes and improvements.

Remote Config usage calculation and billing have changed under the new pricing model.

Starting September 1, 2026, Remote Config introduces usage-based pricing based on daily fetch request volume. Every project includes a no-cost tier of up to 100,000 daily fetches, with pay-as-you-go pricing on the Blaze plan beyond that; all features remain included at no extra cost.

A/B Testing is now integrated directly into Remote Config as a native feature, bringing experiments into the core template lifecycle. Removed support for temperature, top-K, top-P, frequency penalty, presence penalty, and candidate count on gemini-3.7-flash; the latter three cause a 400 error.

A/B Testing now integrates with Remote Config for experiment targeting.

Firebase AI Logic lets you choose between the us and eu locations when using the Agent Platform Gemini API, with new Agent Platform initialization defaulting to global and legacy Vertex AI syntax defaulting to us-central1, to meet compliance, latency, availability, and durability requirements.

All Imagen models, across both Gemini Developer and Agent Platform APIs, shut down on August 17, 2026, and their APIs are removed from Firebase AI Logic SDKs. Migrate apps to a Gemini Image model to restore service. The Unity SDK v13.16.0 also adds features in Firebase AI, FCM, and Remote Config, plus bug fixes.

Imagen models are being shut down. Users should migrate to alternative solutions.

Firebase AI Logic published a security checklist covering best practices for using the service and calling the Gemini API directly from mobile and web apps.

A new security checklist is available to help secure AI-powered applications built with Firebase AI Logic.

This release introduces new features in FCM and Remote Config, changes to App Check, and a bug fix in Authentication, along with other changes and fixes.

Dart functions no longer incorrectly require Dart 3.13.0 or later.

Firebase SDK for Flutter v4.19.0 is now available, bringing changes and bug fixes across several products.

Adds new commands for managing App Check providers and adds web app support for Crashlytics MCP tools, along with several fixes and improvements.

Adds an --immediate flag to ext:uninstall, updates the Pub/Sub and SQL Connect emulators, and includes several other fixes and improvements.

The Firebase JavaScript SDK (v12.18.0) is now available.

This release includes new features in Firebase SQL Connect and dependency updates in Cloud Firestore and Cloud Storage.