I rarely use Facebook Messenger. But I am often given red Messenger badge "unread message" notifications for friendship anniversaries.
The notification causes a red Messenger badge, which is very annoying as you think you are getting a real message. If you are using a mobile app, you also cannot clear the red Messenger badge without installing the separate Facebook Messenger app.
The title of these messages is:
You and FRIEND_NAME are celebrating X years of friendship on Facebook
Opening the message in your inbox displays the message:
Happy Friendversary with FRIEND_NAME
You became friends on Facebook X years ago.
This notification is not a "Facebook Memories" feature, nor a Friendversary Video. It is not in the Timeline. It seems to be a "growth hack" designed to drive usage of Facebook Messenger.
How do I prevent these Friendversary messages from showing up in my inbox and causing the Messenger badge to turn red due to unread messages?