Firebase Cloud Messaging: Send notification with profile photo

Question

Starting with iOS 15 I have noticed more and more chat apps sending push notifications in a new style. Instead of showing a regular notification with a square profile picture on the right side, the image is shown as a circle on the left side, replacing the app icon and the app icon is in the lower right corner of the image. I first noticed this with messages and assumed it was just something Apple could do but now Snapchat and WhatsApp have those notifications as well. Today TikTok stated sending notifications in the same way and I’m determined to find out how I can do this in my apps. Although I have seen a few articles talking about apps that have these notifications, I have not found any information on how to implement them. Is this exclusive to certain apps? Also, if this is available for all apps, is there a way to send these trough Firebase Cloud Messaging?

Ponton