To Solve ReferenceError: Can't find variable: IDBIndex Error Here I am facing this issue in firebase's latest version. So Just downgrading firebase is working fine. Use "firebase": "9.6.7" and now Your error must be solved. First of all delete node_modules. Then delete yarn.lock Now, downgrade firebase to "9.6.7" yarn add firebase@9.6.7. Then download the package using yarn install. Now, your error must be solved. Thank You.