⇧⌘S meant “Save As” for most Mac users for a long time, but all that changed with Mac OS X Lion, when Apple decided to make it mean “Duplicate” for reasons that have never made any sense to anyone.
Instead of just adding an option to “Duplicate” they took the keyboard shortcut that people knew, and hid “Save As” behind the ⌥ key.
Since that day, there has been a way to get “Save As” back, if you were willing to go into System Preferences and setup a global keyboard shortcut.
Simply go to System Preferences » Keyboard » Shortcuts and then click on “App Shortcuts” in the left column. Then click the “+” under the column divider.
That will bring up window where you can enter “Save As…” in the “Menu Title” spot.
Click into the spot next to “Keyboard Shortcut” and press ⇧⌘S. It should look like this when you are done:
Note that it used to be important to make sure that you were using a proper ellipses “…” but it now seems possible to just use three periods “…”
When you are done, the System Preferences window should look something like this:
And you can check an app such as TextEdit to see that “Save As…” has been restored to its rightful spot:
If you do want to use “Duplicate”, you’ll see it is right there under “Save As…”
Copyright 2018 Timothy J. Luoma