A similar insanity happens with window borders in general, because heyaah, wow, minimalism is cool. So when you need to resize a window or, god forbid, drag it by its title bar(), that too is minimized into unrecognisability. To be clear, the problem here is, that you can't tell where window A ends and window B begins, because of design minimalism, so it is simply hard to discern where the drag-border is.
() which leads me to window title-bar anorexia: It has also become oh so popular to minimize and compact the windows title bar, so that there is no area left where your mouse can grab the window to drag it. Web browsers, among many other apps, are guilty of this. The intent behind is to avoid the "double windows top", where you have first the title bar, then the menu below that (they have been collapsed into one); but apparently no one thought about "but how can users then drag their windows?".. I guess we are not supposed to, because the app is supposed to be full-screen maxxed, on the tablet we are drooling on. Or if there is another way, I, director Skinner and Homer's dad did not get the memo.