# Special Use Cases | Sentry for Cloud Functions for Firebase

* #### [Shared Environments / Browser Extensions](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/shared-environments.md)

  Learn how to use Sentry in shared environments (for example in browser extensions or VSCode extensions).

* #### [Micro Frontends](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/micro-frontends.md)

  Learn how to identify the source of errors and route events to different Sentry projects when using micro frontends or module federation.

* #### [Multiple Sentry Instances](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/multiple-sentry-instances.md)

  Learn how to manage several Sentry instances by creating your own clients.

* #### [Offline Caching](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/offline-caching.md)

  Learn how to cache Sentry events while being offline.

* #### [Web Workers](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/web-workers.md)

  Learn how to use Sentry's Browser SDK in Web Workers API.

* #### [Sentry Testkit](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/sentry-testkit.md)

  Learn how to assert that the right flow-tracking or error is being sent to Sentry, but without really sending it to the Sentry servers.

## Pages in this section

- [Shared Environments / Browser Extensions](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/shared-environments.md)
- [Micro Frontends](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/micro-frontends.md)
- [Multiple Sentry Instances](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/multiple-sentry-instances.md)
- [Offline Caching](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/offline-caching.md)
- [Web Workers](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/web-workers.md)
- [Sentry Testkit](https://docs.sentry.io/platforms/javascript/guides/firebase/best-practices/sentry-testkit.md)
