Hi, thanks for your reply. Sorry for the delay. It's not for lack of interest!
I don't generally like two windows open either, though occasionally in writing or publishing projects, it is very handy. But my last message's problem was based on my need to have two iTunes windows to be open, to compare one screen's contents with another window in the same app. If it's not easy for me to buy more songs by comparing what I have to what's available, I don't generally bother.
El Capitan's split screen implies that it is for two different apps to be open at once, so that is not a solution.
Another example of the annoying removal of a feature is the absence of Secure Empty Trash in El Capitan. I know there is a workaround, but it's complicated; here again Apple has taken a perfectly useful feature and dumped it. This is crazy. I will have to go look for an App that accomplishes the same thing with just a click. It will probably cost me money. Why?
I miss the colored folders that go back several OS generations; I see them when I use my old G5. I miss them. They were colorful and easily recognizable; for a long time now, of course, I have a sea of gray folders and icons that don't have the zing for a pair eyes that have nearly 70 years on them.
I don't have any specific documentation, but I am seeing on many occasions over the last six months, a syncing error message in iTunes that states that iTunes was not able to complete the sync because there is not enough room on my iOS device, adding unhelpfully, something like, "769.3MB needed, 3.1 GB available." I will add that this particular Mac still has Yosemite on it, so maybe it's been fixed.
End of rant. Sorry, but I am tired of Apple's continuing to screw around with things that work fine just to make them fit some kind of evolving ideal about what things should look like and how sleek they should be.
Thank you for all your time.
David