https://firebase.googleblog.com/2017/06/keep-your-promises-when-using-cloud.html?fbclid=IwAR2FuvlU2CbwjV-I75q7-WIkJyLHRYT-R3cyleEUWF3Fsq42THMCwZN6by8

  
const ref_p1_state = root.child(`player_states/${game_state.p1uid}`)  
const ref_p2_state = root.child(`player_states/${game_state.p2uid}`)  
const pr_update_p1 = ref_p1_state.update(update_p1)  
const pr_update_p2 = ref_p2_state.update(update_p2)  
  
return Promise.all([pr_update_p1, pr_update_p2])

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https://stackoverflow.com/questions/55430079/promise-all-does-not-wait-for-firestore-query-to-loop