missing collapse buttons
I have recently upgraded to OS 10.11,
I have recently upgraded from os 10.8 to 10.11.so many things not working properly. in a finder window, in list view, with SOME folders, when viewed in their own tab, the folders within the folder do not display the open/collapse triangle. However when viewed within the folder containing that main folder, the triangles do appear. And this happens only with SOME folders, with others, they always display the collapse button. I know that sounds confusing, be grateful for any ideas, tech support has had no clue. I want to go back to Mountain Lion . . ..
iMac (21.5-inch Mid 2011), OS X El Capitan (10.11.6)