Having used Facebook mainly for the messaging functionality for years now, I'm amazed I never knew messenger.com existed. It's interesting to consider that, although I use an ad-blocker, it must be in Facebook's interests to keep people on the main site in order to throw adverts at them, further infiltrate their lives etc.
This. Since I've started using messenger.com, I check facebook.com about once a week. Was really easy to switch and saved a lot of mental energy and attention that would have went for random facebook posts, etc.