desktop icons faded in sierra
Mac mini late 2012 running macOS 10.12.6 Sierra.
For some strange weird reason, "some" of my desktop icons are faded. Plus whenever I want to upload a picture from one of the faded icons when the save drop down window appears none of the faded icons show when I select "desktop". Please note: I learned that I can hit the "shift-command-period (key)" while "desktop" is selected and the icons will magically appear. I know that. Also, I have complete access to the faded icons: They can be opened, moved, etc.
The problem is, how in the world, out-of-the-blue, did some icons become faded while others didn't.
Really baffled. Spent hours trying to find if there's a fix. The only fix I found, without using the terminal, was the above 3-keystroke mentioned above.
Any enlightenment will be greatly appreciated. Thank you. Standing by.
Mac mini, OS X Yosemite (10.10.4), 2.3 GHz/i7/16GB RAM