The MacOS Dropbox app
It used to be a solid app, that was sparse and performant. These days it is a slow resource hog that I don't understand the point with. My gut feeling is that Dropbox tries to turn themselves into a company that does more than to sync that Dropbox folder. I don't want or need that. I've come back to them after years of not using them. And I'd prefer to have the 2015 version of their app back.