[REQUIRED] Environment info

firebase-tools: 13.34.0

Platform: macOs

[REQUIRED] Test case

Environment setup

1. Start up just the auth emulator and export emulator host

firebase emulators:start --only auth --project demo-project

2. Create a user in the emulator AND live environment with the same email: email@example.com

fetchUserByEmail.js

const admin = require('firebase-admin');
admin.initializeApp();

(async () => {
  try {
    const matchingCase = 'email@example.com';
    const user = await admin.auth().getUserByEmail(matchingCase);
    console.log(user); // Logs
  } catch (e) {
    console.error(e); // Doesn't Log
  }
  try {
    const nonMatchingCase = 'EmAiL@eXaMpLe.com';
    const user = await admin.auth().getUserByEmail(nonMatchingCase); // Throws auth/user-not-found
    console.log(user); // Doesn't Log
  } catch (e) {
    console.error(e); // Logs user not found error
  }
  await admin.app().delete();
})();

[REQUIRED] Steps to reproduce

• Run script against emulator:

FIREBASE_AUTH_EMULATOR_HOST=127.0.0.1:9099 \
GCLOUD_PROJECT_ID=demo-project \
node ./fetchUserByEmail.js

• Run script against live data:

GCLOUD_PROJECT_ID=project-live \
node ./fetchUserByEmail.js

[REQUIRED] Expected behavior

The user is found in both environments, regardless of email casing.

[REQUIRED] Actual behavior

The user is found in the live environment, regardless of email casing.
The user is found in the emulator environment when the casing matches,
but throws an auth/user-not-found error when casing does not match.