No folder triangles on desktop only - OS Sierra This just happened tonight.  Without warning and for no reason at all, the little triangle next to the folders on the desktop just disappeared.  So I cannot easily see the contents of the folders, I have to double click them.
  But it's only on the desktop, all other folders have the triangles.
  I only have one display.  I checked all the settings I could and did not see anything.  I don't even know what those triangles are called.
I am SO STUPID.  It's already answered, and it's because I had the "arrange by" set to "name."
  Someone please delete this!