My OS is EC 10.11.6 Say I create a new folder and import images into this folder, the default backgrd color is grey. Under "View Option", it appeared the moment when I change "Arrange By" to any option, the backgrd color will auto changed to white. It seems it will not allowed us to revert back to any colour option despite there is a colour picker. If I recalled, my old com with SL don't seem to restrict in any colour backgrd that we chose. Seems 12 steps backward.