There are many configuration options in Xcode's Build Settings. Some are seldom-used, while some are new. You can check what they do by revealing the Quick Help Inspector (cmd+opt+2 as of writing).

Some of us are on small screens. You can opt-double click on a setting to display a popup showing the same information.

Similarly, opt-click on a symbol (class, function/method) in the code editor to view its documentation.

Pressing the opt key while clicking or double-clicking on macOS often brings up something additional in various apps.