Firebase Emulators UI doesn't show any data

I am starting my emulators with:

`firebase emulators:start --project projectId``

Then on a Python script I am doing:

import os
import firebase_admin
from google.cloud import firestore
os.environ['FIRESTORE_EMULATOR_HOST'] = "localhost:8080"
os.environ['GCLOUD_PROJECT'] = "projectId"
fs_root = firestore.Client()
fs_root.collection('data').document('1').set({'key':'value'})

The data is written, I can retrieve it in Python. But if I check my Emulators UI nothing is there.