Copying into folders - El Capitan

[dazzer21-2]

For some reason, when I'm copying files into a folder in the Finder (ElCap 10.11.4), more often than not the green '+' doesn't appear and the name of the folder is not highlighted as it should be, which makes placing the files a little hit and miss at times. Doesn't happen all the time so it's not a totally broken feature, but it can be a little annoying when trying to do things in a hurry...