Firebase docData stream emits identical object values multiple times in a row

This is my code:

import { doc, docData } from '@angular/fire/firestore';

const gameDocRef = doc(this.firestore, 'game', game.id);
const game$ = docData(gameDocRef, { idField: 'id' })


Somehow the game$ observable emits two identical emissions in a row

Some things to note:

• I am logging and checking: the stream only gets created once
• I am logging and checking: the same exact deep-copy object gets emitted two times
• I am only doing a single request to my firestore-backend and yet this request causes two identical emissions

Of course I could do a distinctUntilXChanged on the observable, but afaik this will still count them as two distinct reads in my firestore quota. This is the main problem I am trying to avoid, I do not want to pay twice as much money for firestore than I actually need to.

This is how I am determining whether the emissions are identical:

const currentGameJSON = JSON.stringify(currentGame);
const newGameJSON = JSON.stringify(game);
if (currentGameJSON === newGameJSON) {
console.error("SAME GAME EMISSION", currentGameJSON);
}


My doc does not have recursive props or anything weird like this, simple JSON.

I do not have firestore persistence enabled.

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