I am also facing this issue.

Here is a minimal repo similar to my project reproducing the issue: https://github.com/jsakas/firebase-test-sakas

It's a firebase, typescript, webpack project with minimal dependencies.

We also see the same error message after upgrading to 8.6.7. It was 8.2.0 before and was working properly.

We also see the same error message after upgrading to 8.6.7. It was 8.2.0 before and was working properly.

Downgraded to 8.6.5 and everything looks fine. "_this.auth.addAuthTokenListener is not a function" This was the problem as mentioned above.

Same when upgrading to 8.6.7 from 8.4.2 with an app using multiple app instances. The error message was:

TypeError: n.auth.addAuthTokenListener is not a function

Immediately followed by:

FirebaseError: Firebase: Firebase App named '[DEFAULT]' already exists (app/duplicate-app).

8.6.5 works fine.

I also have this issue with the same error messages as above. When I removed my firebase app initialization of .firestore() , it then works fine, but I lose access to that database. I have attempted to change package versions of firebase and firestore without success.

I got the same error when I installed firebase 8.6.2

Same as @philsouth47 , firestore initialization is the cause.

I tried 8.6.5, 8.6.7, it does not fix it.
Downgraded to 8.2.0 and all is fine.

Reverting from "^8.6.7" to "8.6.5" worked for me

Thanks for the report. I was able to reproduce the error using the sample project created and shared by @jsakas. I also confirmed that SDK version 8.6.5 worked fine.

I'm trying to get the common denominator here. For those who are getting the similar error, did you use webpack? I tried using a non webpack project and the SDK version 8.6.7 worked fine.

I am using webpack.

Don't know if you saw the detail in the original report, but there's this:

(t) => {
  e.auth = t;  // t is `true` when it's supposed to be some kind of auth object.
  e.auth.addAuthTokenListener(...);
}

One thing I recall seeing is that not only was the parameter named t, but also there was an object in the next outer scope also called t, which might be the object it's meant to refer to?

Maybe an issue with minification?

Kinda guessing, really.

Thanks for the confirmation @tomhicks! We will check this out and update this thread if we have any information to share.

confirm that rolling back to 8.6.5 solved the problem

Just wanted to add that I'm also receiving this same error but am not using webpack. Only using a fairly simple Rollup pipeline.
8.6.6 and 8.6.7 both throw the same error. Reverting back to 8.6.5 resolved things in the meantime. Happy to put together a minimal repo for reproduction if needed.

I'm still having this issue on a new project instance of nuxt with @nuxtjs/axios. Been dealing with it since the latest update.

Thanks for the report. I was able to reproduce the error using the sample project created and shared by @jsakas. I also confirmed that SDK version 8.6.5 worked fine.

I'm trying to get the common denominator here. For those who are getting the similar error, did you use webpack? I tried using a non webpack project and the SDK version 8.6.7 worked fine.

Project was created with npx preact-cli create default my-project

"dependencies": {
    "firebase": "^8.6.8",
    "preact": "^10.5.13",
    "preact-render-to-string": "^5.1.19",
    "preact-router": "^3.2.1"
  },
  "devDependencies": {
    "@babel/core": "^7.14.3",
    "@firebase/rules-unit-testing": "^1.3.2",
    "@storybook/addon-actions": "^6.2.9",
    "@storybook/addon-essentials": "^6.2.9",
    "@storybook/addon-links": "^6.2.9",
    "@storybook/preact": "^6.2.9",
    "@testing-library/preact": "^2.0.1",
    "babel-jest": "^26.6.3",
    "babel-loader": "^8.2.2",
    "core-js": "^3.12.1",
    "cypress": "^7.3.0",
    "eslint": "^7.26.0",
    "eslint-config-google": "^0.14.0",
    "eslint-config-preact": "^1.1.4",
    "eslint-plugin-cypress": "^2.11.3",
    "faker": "^5.5.3",
    "firebase-admin": "^9.9.0",
    "jest": "^26.6.3",
    "jest-preset-preact": "^4.0.3",
    "preact-cli": "^3.2.2",
    "sirv-cli": "^1.0.11",
    "storybook-css-modules-preset": "^1.1.1"
  }