I'm using Firestore to build a web application that has an activity feed. Anytime a user clicks a button on the app, the activity feed of all users that are connected to that button should update with a message. Right now, for each user, there is a reference to an activity feed Object.
The Activity Feed Object contains an array of activity elements. Anytime a user clicks on the button, the activity element should be created and added to the list of each user's Activity feed object.
The users, activity feed, and activity items are in their own collections.
User->Activity Feed->Array(ActivityItem...)
However, I hear that it's not easy to add elements to a Firebase array and I was wondering if there is a different approach I should use. If this is the right approach, how would I update the array of each user's activity feed object?