Description

See docs for instantiating 2nd database: https://firebase.google.com/docs/reference/cpp/class/firebase/firestore/firestore?_gl=1*wpl56g*_up*MQ..*_ga*ODM3Nzk3MTY5LjE3MTkzMTg2ODc.*_ga_CW55HF8NVT*MTcxOTMxODY4Ny4xLjAuMTcxOTMxODY4Ny4wLjAuMA..

Related Issues

closes #12996

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
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Breaking Change

Does your PR require plugin users to manually update their apps to accommodate your change?

• Yes, this is a breaking change.
• No, this is not a breaking change.