I don't want Facebook Messenger, and the Facebook app cannot be uninstalled on my device since it came preinstalled with the Android OS on it (HTC One - it can however be disabled).

Now, if someone uses Facebook Messenger to send me a message, my Facebook app will notify me about unread messages - I've disabled most notifications, but the icon still gets a number increase indicating messages that can be read. These messages cannot be read from within the app without installing Messenger. Using the browser no longer work for reading these messages, since they are pushing the Messenger app.

The only sad part here are the few "friends" that actually write their messages to /dev/null trying to reach me...

I've been contemplating disabling my FB account altogether, but it turns out it is required sometimes for authentication. Spotify being an important one for me.