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.
opt-click on a symbol (class, function/method) in the code editor to view its documentation.
opt key while clicking or double-clicking on macOS often brings up something additional in various apps.