I "actively" have a FB account by most measures, and I don't use Facebook Messenger. I only access their mobile site through Tinfoil for Facebook, and the messaging works just fine in that.
Cool, I hadn't found any browsers that worked well with it mobily and Messenger has become the lowest common denominator for group messaging, among my friends at least, particularly for Android, I've just resigned to using it. I'll check out Tinfoil for Facebook though, thanks.