The NSScreen safeAreaInsets property is macOS 12.  Older SDKs do not declare
it, so the message returns id and qemu 11.1.0 fails with an incompatible
initialisation of NSEdgeInsets.

Screens without a notch report zero insets, so substituting zeros preserves
behaviour.  The guard tests MAC_OS_X_VERSION_MIN_REQUIRED, not MAX_ALLOWED:
this is a runtime message send, so building against a macOS 12 SDK while
targeting an older system must still take the fallback.  Note that +cocoa is a
default variant only at darwin >= 18, so this is reached on 10.14 and 10.15 but
not below.

See https://trac.macports.org/ticket/70482

--- ui/cocoa.m.orig
+++ ui/cocoa.m
@@ -489,7 +489,14 @@
 - (NSSize) screenSafeAreaSize
 {
     NSSize size = [[[self window] screen] frame].size;
+    /* -[NSScreen safeAreaInsets] is macOS 12+; older SDKs do not declare it.
+     * Screens without a notch have zero insets, so this is a no-op there. */
+#if defined(MAC_OS_VERSION_12_0) && \
+    MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_VERSION_12_0
     NSEdgeInsets insets = [[[self window] screen] safeAreaInsets];
+#else
+    NSEdgeInsets insets = NSEdgeInsetsMake(0, 0, 0, 0);
+#endif
     size.width -= insets.left + insets.right;
     size.height -= insets.top + insets.bottom;
     return size;