diff --git a/CHANGES.txt b/CHANGES.txt
index e3d7dbd71..b2ba3c98d 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,4 @@
-Changes in FLTK 1.5.0                                   Released: xxx yy 2025
+Changes in FLTK 1.5.0                                   Released: xxx yy 2026
 
   This is the first FLTK release that exclusively uses CMake to be built.
   autoconf/configure/Makefile support has been removed. If you believe you
@@ -9,7 +9,7 @@ Changes in FLTK 1.5.0                                   Released: xxx yy 2025
 
 
   Platform Specific Fixes and Build Procedure Improvements
-
+  - macOS: required SDK version and deployment target changed to 10.5 or higher
 
   Wayland related Improvements and Fixes
 
@@ -23,7 +23,7 @@ Changes in FLTK 1.5.0                                   Released: xxx yy 2025
   Other Changes
 
   - Removed autotools (configure/make) support
-
+  - Requires C++11 or higher
 
 
 Changes in FLTK 1.4
diff --git a/FL/mac.H b/FL/mac.H
index b0a2b84f5..5133a6ce8 100644
--- a/FL/mac.H
+++ b/FL/mac.H
@@ -1,7 +1,7 @@
 //
 // Mac header file for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2018 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -114,10 +114,6 @@ typedef unsigned int NSUInteger;
 #endif
 #endif
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_4
-typedef CGImageAlphaInfo CGBitmapInfo;
-#endif
-
 struct flCocoaRegion {
   int count;
   CGRect *rects;
diff --git a/src/Fl_cocoa.mm b/src/Fl_cocoa.mm
index 7f12390d2..c6d767990 100644
--- a/src/Fl_cocoa.mm
+++ b/src/Fl_cocoa.mm
@@ -47,6 +47,12 @@ extern "C" {
 #include <string.h>
 #include <pwd.h>
 
+#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5 || \
+    MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5
+# error macOS SDK and deployment target version 10.5 or higher is required.
+// Note: change also the warning in Fl_Darwin_System_Driver::calc_mac_os_version() below
+#endif
+
 #import <Cocoa/Cocoa.h>
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_15_0
 # import <ScreenCaptureKit/ScreenCaptureKit.h>
@@ -198,10 +204,10 @@ const NSUInteger NSWindowStyleMaskFullScreen = NSFullScreenWindowMask;
 const NSUInteger NSEventMaskAny = NSAnyEventMask;
 const NSUInteger NSEventMaskSystemDefined = NSSystemDefinedMask;
 
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
 const NSUInteger NSBitmapFormatAlphaFirst = NSAlphaFirstBitmapFormat;
 const NSUInteger NSBitmapFormatAlphaNonpremultiplied = NSAlphaNonpremultipliedBitmapFormat;
-#  endif
+#define NSEventSubtypeTabletProximity NSTabletProximityEventSubtype
+#define NSEventSubtypeTabletPoint NSTabletPointEventSubtype
 #endif
 
 /*
@@ -569,10 +575,7 @@ void Fl_Cocoa_Screen_Driver::breakMacEventLoop()
 @end
 
 
-@interface FLView : NSView <NSTextInput
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-, NSTextInputClient
-#endif
+@interface FLView : NSView <NSTextInput, NSTextInputClient
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
 ,NSDraggingSource
 #endif
@@ -617,15 +620,7 @@ void Fl_Cocoa_Screen_Driver::breakMacEventLoop()
 - (BOOL)performDragOperation:(id <NSDraggingInfo>)sender;
 - (void)draggingExited:(id < NSDraggingInfo >)sender;
 - (NSDragOperation)draggingSourceOperationMaskForLocal:(BOOL)isLocal;
-#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5
-- (void)insertText:(id)aString replacementRange:(NSRange)replacementRange;
-- (void)setMarkedText:(id)aString selectedRange:(NSRange)newSelection replacementRange:(NSRange)replacementRange;
-- (NSAttributedString *)attributedSubstringForProposedRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
-- (NSRect)firstRectForCharacterRange:(NSRange)aRange actualRange:(NSRangePointer)actualRange;
-- (NSInteger)windowLevel;
-#else
 - (void)updateTrackingAreas;
-#endif
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
 - (NSDragOperation)draggingSession:(NSDraggingSession *)session sourceOperationMaskForDraggingContext:(NSDraggingContext)context;
 - (void)draggingSession:(NSDraggingSession *)session
@@ -651,14 +646,12 @@ void Fl_Cocoa_Screen_Driver::breakMacEventLoop()
 #endif
   [[self standardWindowButton:NSWindowDocumentIconButton] setImage:nil];
   [super close];
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  while (fl_mac_os_version >= 100500) {
+  while (true) {
     NSArray *a = [[self contentView] trackingAreas];
     if ([a count] == 0) break;
     NSTrackingArea *ta = (NSTrackingArea*)[a objectAtIndex:0];
     [[self contentView] removeTrackingArea:ta];
   }
-#endif
   // when a fullscreen window is closed, windowDidResize may be sent after the close message was sent
   // and before the FLWindow receives the final dealloc message
   w = NULL;
@@ -1175,19 +1168,6 @@ static void cocoaMouseHandler(NSEvent *theEvent)
       }
       mods_to_e_state( mods );
       update_e_xy_and_e_xy_root([theEvent window]);
-      if (fl_mac_os_version < 100500) {
-        // before 10.5, mouse moved events aren't sent to borderless windows such as tooltips
-        Fl_Window *tooltip = Fl_Tooltip::current_window();
-        int inside = 0;
-        if (tooltip && tooltip->shown() ) { // check if a tooltip window is currently opened
-          // check if mouse is inside the tooltip
-          inside = (Fl::event_x_root() >= tooltip->x() && Fl::event_x_root() < tooltip->x() + tooltip->w() &&
-                    Fl::event_y_root() >= tooltip->y() && Fl::event_y_root() < tooltip->y() + tooltip->h() );
-        }
-        // if inside, send event to tooltip window instead of background window
-        if (inside)
-          window = tooltip;
-      }
       Fl::handle( sendEvent, window );
       }
       break;
@@ -1292,28 +1272,6 @@ static void orderfront_subwindows(FLWindow *xid)
 }
 @end
 
-@interface FLWindowDelegateBefore10_5 : FLWindowDelegateBefore10_6
--(void)windowDidDeminiaturize:(NSNotification *)notif;
--(void)windowWillMiniaturize:(NSNotification *)notif;
-@end
-@implementation FLWindowDelegateBefore10_5
--(void)windowDidDeminiaturize:(NSNotification *)notif
-{
-  [super windowDidDeminiaturize:notif];
-  fl_lock_function();
-  orderfront_subwindows([notif object]);
-  fl_unlock_function();
-}
--(void)windowWillMiniaturize:(NSNotification *)notif
-{
-  [super fl_windowMiniaturize:notif];
-  NSArray *children = [(NSWindow*)[notif object] childWindows]; // 10.2
-  NSEnumerator *enumerator = [children objectEnumerator];
-  id child;
-  while ((child = [enumerator nextObject]) != nil) [child orderOut:self];
-}
-@end
-
 // compute coordinates of the win top left in FLTK units
 static void CocoatoFLTK(Fl_Window *win, int &x, int &y) {
   NSPoint ori;
@@ -1337,8 +1295,7 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
 + (void)initialize
 {
   if (self == [FLWindowDelegate self]) {
-    if (fl_mac_os_version < 100500) flwindowdelegate_instance = [FLWindowDelegateBefore10_5 alloc];
-    else if (fl_mac_os_version < 100600) flwindowdelegate_instance = [FLWindowDelegateBefore10_6 alloc];
+    if (fl_mac_os_version < 100600) flwindowdelegate_instance = [FLWindowDelegateBefore10_6 alloc];
     else flwindowdelegate_instance = [FLWindowDelegate alloc];
     flwindowdelegate_instance = [flwindowdelegate_instance init];
   }
@@ -1569,7 +1526,7 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
 }
 - (void)windowDidMiniaturize:(NSNotification *)notif
 {
-  if (fl_mac_os_version >= 100500) [self fl_windowMiniaturize:notif];
+  [self fl_windowMiniaturize:notif];
   fl_lock_function();
   FLWindow *nsw = (FLWindow*)[notif object];
   Fl_Window *window = [nsw getFl_Window];
@@ -1822,25 +1779,6 @@ static FLWindowDelegate *flwindowdelegate_instance = nil;
 }
 @end
 
-@interface FLAppDelegateBefore10_5 : FLAppDelegate
-- (void)applicationDidUnhide:(NSNotification *)notify;
-- (void)applicationDidUpdate:(NSNotification *)aNotification;
-@end
-@implementation FLAppDelegateBefore10_5
-- (void)applicationDidUnhide:(NSNotification *)notify
-{ // before 10.5, subwindows are lost when application is unhidden
-  fl_lock_function();
-  for (Fl_X *x = Fl_X::first; x; x = x->next) {
-    if (![(FLWindow*)x->xid parentWindow]) {
-      orderfront_subwindows((FLWindow*)x->xid);
-    }
-  }
-  fl_unlock_function();
-}
-- (void)applicationDidUpdate:(NSNotification *)aNotification
-{
-}
-@end
 
 static void drain_dropped_files_list() {
   open_cb_f_type open_cb = ((FLAppDelegate*)[NSApp delegate])->open_cb;
@@ -1951,7 +1889,7 @@ void Fl_Cocoa_Screen_Driver::open_display_platform() {
     if (need_new_nsapp) [NSApplication sharedApplication];
     NSAutoreleasePool *localPool;
     localPool = [[NSAutoreleasePool alloc] init]; // never released
-    FLAppDelegate *delegate = (Fl_Darwin_System_Driver::calc_mac_os_version() < 100500 ? [FLAppDelegateBefore10_5 alloc] : [FLAppDelegate alloc]);
+    FLAppDelegate *delegate = [FLAppDelegate alloc];
     [(NSApplication*)NSApp setDelegate:[delegate init]];
     if (need_new_nsapp) {
       if (fl_mac_os_version >= 101300 && fl_mac_os_version < 140000 && is_bundled()) {
@@ -2012,8 +1950,7 @@ static int input_method_startup()
   static int retval = -1; // -1: not initialized, 0: not usable, 1: ready for use
   if (retval == -1) {
     fl_open_display();
-    if (fl_mac_os_version >= 100500) {
-      // These symbols are no longer visible in Apple doc.
+      // These symbols require 10.5. They are no longer visible in Apple doc.
       // They do exist in Carbon.framework --> HIToolbox.framework --> TextServices.h
       TSMGetActiveDocument = (TSMGetActiveDocument_type)Fl_Darwin_System_Driver::get_carbon_function("TSMGetActiveDocument");
       TSMSetDocumentProperty = (TSMSetDocumentProperty_type)Fl_Darwin_System_Driver::get_carbon_function("TSMSetDocumentProperty");
@@ -2024,10 +1961,6 @@ static int input_method_startup()
       kTISTypeKeyboardLayout = (CFStringRef)Fl_Darwin_System_Driver::get_carbon_function("kTISTypeKeyboardLayout");
       kTISPropertyInputSourceType = (CFStringRef)Fl_Darwin_System_Driver::get_carbon_function("kTISPropertyInputSourceType");
       retval = (TSMGetActiveDocument && TSMSetDocumentProperty && TSMRemoveDocumentProperty && TISCreateInputSourceList && kTISTypeKeyboardLayout && kTISPropertyInputSourceType ? 1 : 0);
-    } else {
-      KeyScript = (KeyScript_type)Fl_Darwin_System_Driver::get_carbon_function("KeyScript");
-      retval = (KeyScript? 1 : 0);
-    }
   }
   return retval;
 }
@@ -2037,12 +1970,8 @@ void Fl_Cocoa_Screen_Driver::enable_im() {
 
   im_enabled = 1;
 
-  if (fl_mac_os_version >= 100500) {
     ((FLAppDelegate*)[NSApp delegate])->currentDoc = NULL;
     [NSApp updateWindows]; // triggers [FLAppDelegate applicationDidUpdate]
-  }
-  else
-    KeyScript(-7/*smKeyEnableKybds*/);
 }
 
 void Fl_Cocoa_Screen_Driver::disable_im() {
@@ -2050,12 +1979,8 @@ void Fl_Cocoa_Screen_Driver::disable_im() {
 
   im_enabled = 0;
 
-  if (fl_mac_os_version >= 100500) {
     ((FLAppDelegate*)[NSApp delegate])->currentDoc = NULL;
     [NSApp updateWindows]; // triggers [FLAppDelegate applicationDidUpdate]
-  }
-  else
-    KeyScript(smEnableRomanKybdsOnly);
 }
 
 
@@ -2578,6 +2503,9 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
   NSUInteger mods = [theEvent modifierFlags];
   NSString *pure = [theEvent charactersIgnoringModifiers];
   // detect Function+e to open character palette
+#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_12
+#define NSEventModifierFlagFunction NSFunctionKeyMask
+#endif
   if ((mods & NSEventModifierFlagFunction) && [pure isEqualToString:@"e"] ) {
       [NSApp orderFrontCharacterPalette:self];
       return YES;
@@ -2664,9 +2592,7 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
   cocoaTabletHandler(theEvent, true);
 }
 #endif
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 - (void)updateTrackingAreas {
-  if (fl_mac_os_version >= 100500) {
     if (![[self window] parentWindow]) {
       while (true) {
         NSArray *a = [self trackingAreas]; // 10.5
@@ -2686,9 +2612,7 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
       }
     }
     [super updateTrackingAreas];
-  }
 }
-#endif
 - (void)mouseDragged:(NSEvent *)theEvent {
   cocoaMouseHandler(theEvent);
 }
@@ -3095,13 +3019,7 @@ static FLTextInputContext* fltextinputcontext_instance = nil;
   return [[self window] level];
 }
 
-- (
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-   NSInteger
-#else
-   long
-#endif
-)conversationIdentifier {
+- (NSInteger)conversationIdentifier {
   return identifier;
 }
 
@@ -3866,9 +3784,7 @@ Fl_Quartz_Copy_Surface_Driver::~Fl_Quartz_Copy_Surface_Driver()
 {
   CGContextRestoreGState(gc);
   CGContextEndPage(gc);
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (fl_mac_os_version >= 100500) CGPDFContextClose(gc); // needs 10.5, necessary with macOS 10.15
-#endif
+  CGPDFContextClose(gc); // needs 10.5, necessary with macOS 10.15
   CGContextRelease(gc);
   NSPasteboard *clip = [NSPasteboard generalPasteboard];
   [clip declareTypes:[NSArray arrayWithObjects:PDF_pasteboard_type, TIFF_pasteboard_type, nil] owner:nil];
@@ -4331,7 +4247,6 @@ static void createAppleMenu(void)
     [print_with_titlebar_item setEnabled:YES];
     [appleMenu addItem:[NSMenuItem separatorItem]];
     }
-  if (fl_mac_os_version >= 100400) { // services+hide+quit already in menu in OS 10.3
     // Services Menu
     services = [[NSMenu alloc] initWithTitle:@""];
     menuItem = [appleMenu
@@ -4366,7 +4281,7 @@ static void createAppleMenu(void)
                                     action:@selector(terminate:)
                              keyEquivalent:@"q"];
     [menuItem setTarget:about];
-    }
+
   /* Put menu into the menubar */
   menuItem = [[NSMenuItem alloc] initWithTitle:@"" action:nil keyEquivalent:@""];
   [menuItem setSubmenu:appleMenu];
@@ -4574,8 +4489,7 @@ static void write_bitmap_inside(NSBitmapImageRep *to, int to_width, NSBitmapImag
  */
 {
   const uchar *from_data = [from bitmapData];
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400) { // 10.4 required by the bitmapFormat message
+  // 10.4 required by the bitmapFormat message
     if (([to bitmapFormat] & NSBitmapFormatAlphaFirst) &&
         !([from bitmapFormat] & NSBitmapFormatAlphaFirst) ) {
       // "to" is ARGB and "from" is RGBA --> convert "from" to ARGB
@@ -4588,8 +4502,6 @@ static void write_bitmap_inside(NSBitmapImageRep *to, int to_width, NSBitmapImag
       // so ARGBARGB becomes RGBARGB(A) as needed
       from_data++;
     }
-  }
-#endif
   int to_w = (int)[to pixelsWide]; // pixel width of "to"
   int from_w = (int)[from pixelsWide]; // pixel width of "from"
   int from_h = (int)[from pixelsHigh]; // pixel height of "from"
@@ -4693,13 +4605,11 @@ static NSBitmapImageRep* rect_to_NSBitmapImageRep(Fl_Window *win, int x, int y,
         int view_h = [winview frame].size.height;
         rect = NSMakeRect(int(x*s), int(view_h-y*s-int(h*s)), int(w*s), int(h*s));
         // lock focus to win's view
-  #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
         if (fl_mac_os_version >= 101100) {
           NSGraphicsContext *ctxt = [fl_xid(win)
                                      performSelector:@selector(graphicsContext)];
           [ctxt saveGraphicsState]; // necessary under 10.11
         }
-  #endif
         [winview performSelector:@selector(lockFocus)];
       }
       // The image depth is 3 until macOS 10.5 and 4 with 10.6 and above
@@ -4710,13 +4620,11 @@ static NSBitmapImageRep* rect_to_NSBitmapImageRep(Fl_Window *win, int x, int y,
 #pragma clang diagnostic pop
       if ( !( through_Fl_X_flush && Fl_Window::current() == win) ) {
         [winview performSelector:@selector(unlockFocus)];
-  #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
         if (fl_mac_os_version >= 101100) {
           NSGraphicsContext *ctxt = [fl_xid(win)
                                      performSelector:@selector(graphicsContext)];
           [ctxt restoreGraphicsState];
         }
-  #endif
       }
     }
   return bitmap;
@@ -4774,24 +4682,9 @@ CGImageRef Fl_Cocoa_Window_Driver::CGImage_from_window_rect(int x, int y, int w,
 {
   CGImageRef img;
   NSBitmapImageRep *bitmap = rect_to_NSBitmapImageRep_subwins(pWindow, x, y, w, h, capture_subwins);
-  if (fl_mac_os_version >= 100500) {
     img = (CGImageRef)[bitmap performSelector:@selector(CGImage)]; // requires Mac OS 10.5
     CGImageRetain(img);
     [bitmap release];
-  } else {
-    CGColorSpaceRef cspace = CGColorSpaceCreateDeviceRGB();
-    CGDataProviderRef provider =
-    CGDataProviderCreateWithData(bitmap, [bitmap bitmapData],
-                                 [bitmap bytesPerRow] * [bitmap pixelsHigh],
-                                 nsbitmapProviderReleaseData);
-    img = CGImageCreate([bitmap pixelsWide], [bitmap pixelsHigh], 8, [bitmap bitsPerPixel],
-                        [bitmap bytesPerRow], cspace,
-                        ([bitmap bitsPerPixel] == 32 ? kCGImageAlphaPremultipliedLast :
-                          kCGImageAlphaNone) ,
-                        provider, NULL, false, kCGRenderingIntentDefault);
-    CGColorSpaceRelease(cspace);
-    CGDataProviderRelease(provider);
-  }
   return img;
 }
 
@@ -4899,7 +4792,6 @@ static CGImageRef capture_decorated_window_SCK(NSWindow *nswin) {
 CGImageRef Fl_Cocoa_Window_Driver::capture_decorated_window_10_5(NSWindow *nswin) {
   // usable with 10.5 and above
   CGImageRef img = NULL;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 #  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_VERSION_15_0 && defined(__BLOCKS__)
   if (fl_mac_os_version >= 150000)
       img = capture_decorated_window_SCK(nswin);
@@ -4913,7 +4805,6 @@ CGImageRef Fl_Cocoa_Window_Driver::capture_decorated_window_10_5(NSWindow *nswin
       CFRelease(array);
 #  endif
     }
-#endif // >= MAC_OS_X_VERSION_10_5
   return img;
 }
 
@@ -4988,6 +4879,8 @@ int Fl_Darwin_System_Driver::calc_mac_os_version() {
 #if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_14
   if (fl_mac_os_version >= 101400) views_use_CA = YES;
 #endif
+  if (fl_mac_os_version < 100500)
+    fprintf(stderr, "Warning: FLTK expects macOS version 10.5 or higher");
   return fl_mac_os_version;
 }
 
@@ -5059,7 +4952,6 @@ static NSImage* rgb_to_nsimage(const Fl_RGB_Image *rgb) {
   int ld = rgb->ld();
   if (!ld) ld = rgb->data_w() * rgb->d();
   NSImage *win_icon = nil;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (fl_mac_os_version >= 101000) {
     NSBitmapImageRep *bitmap =
     [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL
@@ -5079,7 +4971,6 @@ static NSImage* rgb_to_nsimage(const Fl_RGB_Image *rgb) {
     [win_icon addRepresentation:bitmap];
     [bitmap release];
   }
-#endif
   return win_icon;
 }
 
diff --git a/src/Fl_get_key_mac.cxx b/src/Fl_get_key_mac.cxx
index ef5ef1ae1..b9ad86dd1 100644
--- a/src/Fl_get_key_mac.cxx
+++ b/src/Fl_get_key_mac.cxx
@@ -1,7 +1,7 @@
 //
 // MacOS keyboard state routines for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2023 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -28,154 +28,7 @@
 
 // The list of Mac OS virtual keycodes appears with OS 10.5 in
 // ...../Carbon.framework/Frameworks/HIToolbox.framework/Headers/Events.h
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 #include <Carbon/Carbon.h>
-#else
-/*
- *    These constants are the virtual keycodes defined originally in
- *    Inside Mac Volume V, pg. V-191. They identify physical keys on a
- *    keyboard. Those constants with "ANSI" in the name are labeled
- *    according to the key position on an ANSI-standard US keyboard.
- *    For example, kVK_ANSI_A indicates the virtual keycode for the key
- *    with the letter 'A' in the US keyboard layout. Other keyboard
- *    layouts may have the 'A' key label on a different physical key;
- *    in this case, pressing 'A' will generate a different virtual
- *    keycode.
- */
-enum {
-  kVK_ANSI_A                    = 0x00,
-  kVK_ANSI_S                    = 0x01,
-  kVK_ANSI_D                    = 0x02,
-  kVK_ANSI_F                    = 0x03,
-  kVK_ANSI_H                    = 0x04,
-  kVK_ANSI_G                    = 0x05,
-  kVK_ANSI_Z                    = 0x06,
-  kVK_ANSI_X                    = 0x07,
-  kVK_ANSI_C                    = 0x08,
-  kVK_ANSI_V                    = 0x09,
-  kVK_ANSI_B                    = 0x0B,
-  kVK_ANSI_Q                    = 0x0C,
-  kVK_ANSI_W                    = 0x0D,
-  kVK_ANSI_E                    = 0x0E,
-  kVK_ANSI_R                    = 0x0F,
-  kVK_ANSI_Y                    = 0x10,
-  kVK_ANSI_T                    = 0x11,
-  kVK_ANSI_1                    = 0x12,
-  kVK_ANSI_2                    = 0x13,
-  kVK_ANSI_3                    = 0x14,
-  kVK_ANSI_4                    = 0x15,
-  kVK_ANSI_6                    = 0x16,
-  kVK_ANSI_5                    = 0x17,
-  kVK_ANSI_Equal                = 0x18,
-  kVK_ANSI_9                    = 0x19,
-  kVK_ANSI_7                    = 0x1A,
-  kVK_ANSI_Minus                = 0x1B,
-  kVK_ANSI_8                    = 0x1C,
-  kVK_ANSI_0                    = 0x1D,
-  kVK_ANSI_RightBracket         = 0x1E,
-  kVK_ANSI_O                    = 0x1F,
-  kVK_ANSI_U                    = 0x20,
-  kVK_ANSI_LeftBracket          = 0x21,
-  kVK_ANSI_I                    = 0x22,
-  kVK_ANSI_P                    = 0x23,
-  kVK_ANSI_L                    = 0x25,
-  kVK_ANSI_J                    = 0x26,
-  kVK_ANSI_Quote                = 0x27,
-  kVK_ANSI_K                    = 0x28,
-  kVK_ANSI_Semicolon            = 0x29,
-  kVK_ANSI_Backslash            = 0x2A,
-  kVK_ANSI_Comma                = 0x2B,
-  kVK_ANSI_Slash                = 0x2C,
-  kVK_ANSI_N                    = 0x2D,
-  kVK_ANSI_M                    = 0x2E,
-  kVK_ANSI_Period               = 0x2F,
-  kVK_ANSI_Grave                = 0x32,
-  kVK_ANSI_KeypadDecimal        = 0x41,
-  kVK_ANSI_KeypadMultiply       = 0x43,
-  kVK_ANSI_KeypadPlus           = 0x45,
-  kVK_ANSI_KeypadClear          = 0x47,
-  kVK_ANSI_KeypadDivide         = 0x4B,
-  kVK_ANSI_KeypadEnter          = 0x4C,
-  kVK_ANSI_KeypadMinus          = 0x4E,
-  kVK_ANSI_KeypadEquals         = 0x51,
-  kVK_ANSI_Keypad0              = 0x52,
-  kVK_ANSI_Keypad1              = 0x53,
-  kVK_ANSI_Keypad2              = 0x54,
-  kVK_ANSI_Keypad3              = 0x55,
-  kVK_ANSI_Keypad4              = 0x56,
-  kVK_ANSI_Keypad5              = 0x57,
-  kVK_ANSI_Keypad6              = 0x58,
-  kVK_ANSI_Keypad7              = 0x59,
-  kVK_ANSI_Keypad8              = 0x5B,
-  kVK_ANSI_Keypad9              = 0x5C
-};
-
-/* keycodes for keys that are independent of keyboard layout*/
-enum {
-  kVK_Return                    = 0x24,
-  kVK_Tab                       = 0x30,
-  kVK_Space                     = 0x31,
-  kVK_Delete                    = 0x33,
-  kVK_Escape                    = 0x35,
-  kVK_Command                   = 0x37,
-  kVK_Shift                     = 0x38,
-  kVK_CapsLock                  = 0x39,
-  kVK_Option                    = 0x3A,
-  kVK_Control                   = 0x3B,
-  kVK_RightShift                = 0x3C,
-  kVK_RightOption               = 0x3D,
-  kVK_RightControl              = 0x3E,
-  kVK_Function                  = 0x3F,
-  kVK_F17                       = 0x40,
-  kVK_VolumeUp                  = 0x48,
-  kVK_VolumeDown                = 0x49,
-  kVK_Mute                      = 0x4A,
-  kVK_F18                       = 0x4F,
-  kVK_F19                       = 0x50,
-  kVK_F20                       = 0x5A,
-  kVK_F5                        = 0x60,
-  kVK_F6                        = 0x61,
-  kVK_F7                        = 0x62,
-  kVK_F3                        = 0x63,
-  kVK_F8                        = 0x64,
-  kVK_F9                        = 0x65,
-  kVK_F11                       = 0x67,
-  kVK_F13                       = 0x69,
-  kVK_F16                       = 0x6A,
-  kVK_F14                       = 0x6B,
-  kVK_F10                       = 0x6D,
-  kVK_F12                       = 0x6F,
-  kVK_F15                       = 0x71,
-  kVK_Help                      = 0x72,
-  kVK_Home                      = 0x73,
-  kVK_PageUp                    = 0x74,
-  kVK_ForwardDelete             = 0x75,
-  kVK_F4                        = 0x76,
-  kVK_End                       = 0x77,
-  kVK_F2                        = 0x78,
-  kVK_PageDown                  = 0x79,
-  kVK_F1                        = 0x7A,
-  kVK_LeftArrow                 = 0x7B,
-  kVK_RightArrow                = 0x7C,
-  kVK_DownArrow                 = 0x7D,
-  kVK_UpArrow                   = 0x7E
-};
-
-/* ISO keyboards only*/
-enum {
-  kVK_ISO_Section               = 0x0A
-};
-
-/* JIS keyboards only*/
-enum {
-  kVK_JIS_Yen                   = 0x5D,
-  kVK_JIS_Underscore            = 0x5E,
-  kVK_JIS_KeypadComma           = 0x5F,
-  kVK_JIS_Eisu                  = 0x66,
-  kVK_JIS_Kana                  = 0x68
-};
-
-#endif
 
 // convert an FLTK (X) keysym to a MacOS symbol:
 // This table is in numeric order by FLTK symbol order for binary search.
@@ -245,33 +98,5 @@ int Fl_Cocoa_Screen_Driver::event_key(int k) {
 
 //: returns true, if that key is pressed right now
 int Fl_Cocoa_Screen_Driver::get_key(int k) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (&CGEventSourceKeyState != NULL) {
-    return (int)CGEventSourceKeyState(kCGEventSourceStateCombinedSessionState, fltk2mac(k) );
-    }
-  else
-#endif
-  {
-  typedef UInt32 fl_KeyMap[4];
-  fl_KeyMap foo;
-  // use the GetKeys Carbon function
-  typedef void (*keymap_f)(fl_KeyMap);
-  static keymap_f f = NULL;
-    if (!f) f = ( keymap_f )Fl_Darwin_System_Driver::get_carbon_function("GetKeys");
-  (*f)(foo);
-#ifdef MAC_TEST_FOR_KEYCODES
- static int cnt = 0;
- if (cnt++>1024) {
-  cnt = 0;
-  printf("%08x %08x %08x %08x\n", (ulong*)(foo)[3], (ulong*)(foo)[2], (ulong*)(foo)[1], (ulong*)(foo)[0]);
- }
-#endif
-  unsigned char *b = (unsigned char*)foo;
-  // KP_Enter can be at different locations for Powerbooks vs. desktop Macs
-  if (k==FL_KP_Enter) {
-    return (((b[0x34>>3]>>(0x34&7))&1)||((b[0x4c>>3]>>(0x4c&7))&1));
-  }
-  int i = fltk2mac(k);
-  return (b[i>>3]>>(i&7))&1;
-  }
+  return (int)CGEventSourceKeyState(kCGEventSourceStateCombinedSessionState, fltk2mac(k) ); // 10.4
 }
diff --git a/src/drivers/Cocoa/Fl_Cocoa_Gl_Window_Driver.mm b/src/drivers/Cocoa/Fl_Cocoa_Gl_Window_Driver.mm
index d286d46f3..6dff548f0 100644
--- a/src/drivers/Cocoa/Fl_Cocoa_Gl_Window_Driver.mm
+++ b/src/drivers/Cocoa/Fl_Cocoa_Gl_Window_Driver.mm
@@ -1,7 +1,7 @@
 //
 // Class Fl_Cocoa_Gl_Window_Driver for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2021-2022 by Bill Spitzak and others.
+// Copyright 2021-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -112,10 +112,8 @@ static NSOpenGLPixelFormat* mode_to_NSOpenGLPixelFormat(int m, const int *alistp
       //list[n++] = AGL_STEREO;
       attribs[n++] = 6/*NSOpenGLPFAStereo*/;
     }
-    if ((m & FL_MULTISAMPLE) && fl_mac_os_version >= 100400) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
+    if (m & FL_MULTISAMPLE) {
       attribs[n++] = NSOpenGLPFAMultisample; // 10.4
-#endif
       attribs[n++] = NSOpenGLPFASampleBuffers; attribs[n++] = (NSOpenGLPixelFormatAttribute)1;
       attribs[n++] = NSOpenGLPFASamples; attribs[n++] = (NSOpenGLPixelFormatAttribute)4;
     }
@@ -480,8 +478,6 @@ Fl_RGB_Image* Fl_Cocoa_Gl_Window_Driver::capture_gl_rectangle(int x, int y, int
   if (factor != 1) {
     w *= factor; h *= factor; x *= factor; y *= factor;
   }
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (fl_mac_os_version >= 100500) {
     NSWindow *nswin = (NSWindow*)fl_mac_xid(pWindow);
     CGImageRef img_full = Fl_Cocoa_Window_Driver::capture_decorated_window_10_5(nswin);
     int bt =  [nswin frame].size.height - [[nswin contentView] frame].size.height;
@@ -492,8 +488,6 @@ Fl_RGB_Image* Fl_Cocoa_Gl_Window_Driver::capture_gl_rectangle(int x, int y, int
     Fl_RGB_Image *rgb = cgimage_to_rgb4(cgimg);
     CGImageRelease(cgimg);
     return rgb;
-  }
-#endif
   [(NSOpenGLContext*)glw->context() makeCurrentContext];
 // to capture also the overlay and for directGL demo
   [(NSOpenGLContext*)glw->context() flushBuffer];
diff --git a/src/drivers/Cocoa/Fl_Cocoa_Printer_Driver.mm b/src/drivers/Cocoa/Fl_Cocoa_Printer_Driver.mm
index 0df98af7e..f1a769d75 100644
--- a/src/drivers/Cocoa/Fl_Cocoa_Printer_Driver.mm
+++ b/src/drivers/Cocoa/Fl_Cocoa_Printer_Driver.mm
@@ -1,7 +1,7 @@
 //
 // Mac OS X-specific printing support (objective-c++) for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2024 by Bill Spitzak and others.
+// Copyright 2010-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -107,8 +107,6 @@ int Fl_Cocoa_Printer_Driver::begin_job (int pagecount, int *frompage, int *topag
   OSStatus status = 0;
   fl_open_display();
   Fl_Cocoa_Window_Driver::q_release_context();
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (fl_mac_os_version >= 100500) {
     NSPrintInfo *info = [NSPrintInfo sharedPrintInfo];
     NSPrintPanel *panel = [NSPrintPanel printPanel];
     //from 10.5
@@ -143,59 +141,6 @@ int Fl_Cocoa_Printer_Driver::begin_job (int pagecount, int *frompage, int *topag
       if (*topage > pagecount && pagecount > 0) *topage = pagecount;
     }
     status = PMSessionBeginCGDocumentNoDialog(printSession, printSettings, pageFormat);//from 10.4
-  }
-  else
-#endif
-  {
-#if !defined(__LP64__) || !__LP64__
-    Boolean accepted;
-    status = PMCreateSession(&printSession);
-    if (status != noErr) return 1;
-    status = PMCreatePageFormat(&pageFormat);
-    status = PMSessionDefaultPageFormat(printSession, pageFormat);
-    if (status != noErr) return 1;
-    // get pointer to the PMSessionPageSetupDialog Carbon function
-    typedef OSStatus (*dialog_f)(PMPrintSession, PMPageFormat, Boolean *);
-    static dialog_f f = NULL;
-    if (!f) f = (dialog_f)Fl_Darwin_System_Driver::get_carbon_function("PMSessionPageSetupDialog");
-    status = (*f)(printSession, pageFormat, &accepted);
-    if (status != noErr || !accepted) {
-      Fl::first_window()->show();
-      return 1;
-    }
-    status = PMCreatePrintSettings(&printSettings);
-    if (status != noErr || printSettings == kPMNoPrintSettings) return 1;
-    status = PMSessionDefaultPrintSettings (printSession, printSettings);
-    if (status != noErr) return 1;
-    PMSetPageRange(printSettings, 1, (UInt32)kPMPrintAllPages);
-    // get pointer to the PMSessionPrintDialog Carbon function
-    typedef OSStatus (*dialog_f2)(PMPrintSession, PMPrintSettings, PMPageFormat, Boolean *);
-    static dialog_f2 f2 = NULL;
-    if (!f2) f2 = (dialog_f2)Fl_Darwin_System_Driver::get_carbon_function("PMSessionPrintDialog");
-    status = (*f2)(printSession, printSettings, pageFormat, &accepted);
-    if (!accepted) status = kPMCancel;
-    if (status != noErr) {
-      Fl::first_window()->show();
-      return 1;
-    }
-    UInt32 from32, to32;
-    PMGetFirstPage(printSettings, &from32);
-    if (frompage) *frompage = (int)from32;
-    PMGetLastPage(printSettings, &to32);
-    if (topage) *topage = (int)to32;
-    if(topage && *topage > pagecount) *topage = pagecount;
-    CFStringRef mystring[1];
-    mystring[0] = kPMGraphicsContextCoreGraphics;
-    CFArrayRef array = CFArrayCreate(NULL, (const void **)mystring, 1, &kCFTypeArrayCallBacks);
-    PMSessionSetDocumentFormatGeneration_type PMSessionSetDocumentFormatGeneration =
-      (PMSessionSetDocumentFormatGeneration_type)Fl_Darwin_System_Driver::get_carbon_function("PMSessionSetDocumentFormatGeneration");
-    status = PMSessionSetDocumentFormatGeneration(printSession, kPMDocumentFormatDefault, array, NULL);
-    CFRelease(array);
-    PMSessionBeginDocumentNoDialog_type PMSessionBeginDocumentNoDialog =
-      (PMSessionBeginDocumentNoDialog_type)Fl_Darwin_System_Driver::get_carbon_function("PMSessionBeginDocumentNoDialog");
-    status = PMSessionBeginDocumentNoDialog(printSession, printSettings, pageFormat);
-#endif //__LP64__
-  }
 
   if (status != noErr) {
     if (perr_message) {
@@ -309,19 +254,7 @@ int Fl_Cocoa_Printer_Driver::begin_page (void)
 {
   OSStatus status = PMSessionBeginPageNoDialog(printSession, pageFormat, NULL);
   CGContextRef gc;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if ( &PMSessionGetCGGraphicsContext != NULL ) {
-    status = PMSessionGetCGGraphicsContext(printSession, &gc);
-  }
-  else
-#endif
-  {
-#if !defined(__LP64__) || !__LP64__
-    PMSessionGetGraphicsContext_type PMSessionGetGraphicsContext =
-      (PMSessionGetGraphicsContext_type)Fl_Darwin_System_Driver::get_carbon_function("PMSessionGetGraphicsContext");
-    status = PMSessionGetGraphicsContext(printSession, NULL, (void **)&gc);
-#endif
-  }
+  status = PMSessionGetCGGraphicsContext(printSession, &gc); // 10.4
   driver()->gc(gc);
   Fl_Surface_Device::push_current(this);
   PMRect pmRect;
@@ -377,13 +310,6 @@ void Fl_Cocoa_Printer_Driver::end_job (void)
     fl_alert ("PM Session error %d", (int)status);
   }
   PMSessionEndDocumentNoDialog(printSession);
-#if !defined(__LP64__) || !__LP64__
-  if (fl_mac_os_version < 100500) {
-    PMRelease(printSettings);
-    PMRelease(pageFormat);
-    PMRelease(printSession);
-    }
-#endif
   Fl_Window *w = Fl::first_window();
   if (w) w->show();
 }
diff --git a/src/drivers/Cocoa/Fl_Cocoa_Window_Driver.cxx b/src/drivers/Cocoa/Fl_Cocoa_Window_Driver.cxx
index 15983032f..ac99ab70b 100644
--- a/src/drivers/Cocoa/Fl_Cocoa_Window_Driver.cxx
+++ b/src/drivers/Cocoa/Fl_Cocoa_Window_Driver.cxx
@@ -1,7 +1,7 @@
 //
 // Definition of Apple Cocoa window driver.
 //
-// Copyright 1998-2018 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -75,12 +75,10 @@ void Fl_Cocoa_Window_Driver::draw_begin()
   if (!Fl_Surface_Device::surface()->driver()->has_feature(Fl_Graphics_Driver::NATIVE)) return;
   CGContextRef my_gc = (CGContextRef)Fl_Surface_Device::surface()->driver()->gc();
   if (shape_data_) {
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-    if (shape_data_->mask && (&CGContextClipToMask != NULL)) {
+    if (shape_data_->mask) {
       CGContextClipToMask(my_gc, CGRectMake(0,0,w(),h()), shape_data_->mask); // requires Mac OS 10.4
     }
     CGContextSaveGState(my_gc);
-# endif
   }
 }
 
@@ -111,12 +109,10 @@ void Fl_Cocoa_Window_Driver::draw_end()
       }
     }
   }
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (Fl_Surface_Device::surface()->driver()->has_feature(Fl_Graphics_Driver::NATIVE)) {
     CGContextRef my_gc = (CGContextRef)Fl_Surface_Device::surface()->driver()->gc();
     if (shape_data_) CGContextRestoreGState(my_gc);
   }
-# endif
 }
 
 
@@ -187,7 +183,6 @@ void Fl_Cocoa_Window_Driver::shape_alpha_(Fl_Image* img, int offset) {
 
 
 void Fl_Cocoa_Window_Driver::shape(const Fl_Image* img) {
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (shape_data_) {
     if (shape_data_->mask) { CGImageRelease(shape_data_->mask); }
   }
@@ -203,7 +198,6 @@ void Fl_Cocoa_Window_Driver::shape(const Fl_Image* img) {
   else if (d == 0) shape_bitmap_((Fl_Image*)img);
   else if (d == 2 || d == 4) shape_alpha_((Fl_Image*)img, d - 1);
   else if ((d == 1 || d == 3) && img->count() == 1) shape_alpha_((Fl_Image*)img, 0);
-#endif
   pWindow->border(false);
 }
 
diff --git a/src/drivers/Darwin/Fl_Darwin_System_Driver.cxx b/src/drivers/Darwin/Fl_Darwin_System_Driver.cxx
index 431e908a5..c11a95f94 100644
--- a/src/drivers/Darwin/Fl_Darwin_System_Driver.cxx
+++ b/src/drivers/Darwin/Fl_Darwin_System_Driver.cxx
@@ -1,7 +1,7 @@
 //
 // Definition of Apple Darwin system driver.
 //
-// Copyright 1998-2021 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -24,9 +24,7 @@
 #include <FL/fl_draw.H>
 #include "../../flstring.h"
 #include <string.h>
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-#include <xlocale.h>
-#endif
+#include <xlocale.h> // 10.4
 #include <locale.h>
 #include <stdio.h>
 #include <dlfcn.h>
@@ -66,61 +64,28 @@ int Fl_Darwin_System_Driver::arg_and_value(const char *name, const char *value)
   return strcmp(name, "NSDocumentRevisionsDebugMode") == 0;
 }
 
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
 static locale_t postscript_locale = NULL;
-#endif
 
 int Fl_Darwin_System_Driver::clocale_vprintf(FILE *output, const char *format, va_list args) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400) {
-    if (!postscript_locale)
-      postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
-    return vfprintf_l(output, postscript_locale, format, args);
-  }
-#endif
-  char *saved_locale = setlocale(LC_NUMERIC, NULL);
-  setlocale(LC_NUMERIC, "C");
-  int retval = vfprintf(output, format, args);
-  setlocale(LC_NUMERIC, saved_locale);
-  return retval;
+  if (!postscript_locale)
+    postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
+  return vfprintf_l(output, postscript_locale, format, args); // 10.4
 }
 
 int Fl_Darwin_System_Driver::clocale_vsnprintf(char *output, size_t output_size, const char *format, va_list args) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400) {
-    if (!postscript_locale)
-      postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
-    return vsnprintf_l(output, output_size, postscript_locale, format, args);
-  }
-#endif
-  char *saved_locale = setlocale(LC_NUMERIC, NULL);
-  setlocale(LC_NUMERIC, "C");
-  int retval = vsnprintf(output, output_size, format, args);
-  setlocale(LC_NUMERIC, saved_locale);
-  return retval;
+  if (!postscript_locale)
+    postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
+  return vsnprintf_l(output, output_size, postscript_locale, format, args); // 10.4
 }
 
 int Fl_Darwin_System_Driver::clocale_vsscanf(const char *input, const char *format, va_list args) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400) {
-    if (!postscript_locale)
-      postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
-    return vsscanf_l(input, postscript_locale, format, args);
-  }
-#endif
-  char *saved_locale = setlocale(LC_NUMERIC, NULL);
-  setlocale(LC_NUMERIC, "C");
-  int retval = vsscanf(input, format, args);
-  setlocale(LC_NUMERIC, saved_locale);
-  return retval;
+  if (!postscript_locale)
+    postscript_locale = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
+  return vsscanf_l(input, postscript_locale, format, args); // 10.4
 }
 
 
-/* Returns the address of a Carbon function after dynamically loading the Carbon library if needed.
- Supports old Mac OS X versions that may use a couple of Carbon calls:
- GetKeys used by OS X 10.3 or before (in Fl::get_key())
- PMSessionPageSetupDialog and PMSessionPrintDialog used by 10.4 or before (in Fl_Printer::begin_job())
- */
+// Returns the address of a Carbon function after dynamically loading the Carbon library if needed.
 void *Fl_Darwin_System_Driver::get_carbon_function(const char *function_name) {
   static void *carbon = ::dlopen("/System/Library/Frameworks/Carbon.framework/Carbon", RTLD_LAZY);
   return (carbon ? dlsym(carbon, function_name) : NULL);
diff --git a/src/drivers/Quartz/Fl_Font.H b/src/drivers/Quartz/Fl_Font.H
index c700568a2..f1a710eea 100644
--- a/src/drivers/Quartz/Fl_Font.H
+++ b/src/drivers/Quartz/Fl_Font.H
@@ -1,7 +1,7 @@
 //
 // Font definitions for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2018 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -31,15 +31,9 @@ class Fl_Quartz_Font_Descriptor : public Fl_Font_Descriptor {
 public:
   Fl_Quartz_Font_Descriptor(const char* fontname, Fl_Fontsize size);
   virtual FL_EXPORT ~Fl_Quartz_Font_Descriptor();
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   CTFontRef fontref;
   // the unicode span is divided in 512 blocks of 128 characters
   float *width[512]; // array of arrays of character widths
-# endif
-# if HAS_ATSU
-  ATSUTextLayout layout;
-  ATSUStyle style;
-# endif
   short q_width;
 };
 
diff --git a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.H b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.H
index ca1ffce04..0afc7369e 100644
--- a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.H
+++ b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.H
@@ -2,7 +2,7 @@
 // Definition of Apple Quartz graphics driver
 // for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2022 by Bill Spitzak and others.
+// Copyright 2010-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -27,16 +27,6 @@
 #include <FL/Fl_Graphics_Driver.H>
 #include <ApplicationServices/ApplicationServices.h>
 
-// condition for the ATSU API to be available at compile time
-#if (    (!defined(__LP64__) || !__LP64__) \
-      && MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_11 \
-      && MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5 \
-    )
-#define HAS_ATSU 1
-#else
-#define HAS_ATSU 0
-#endif
-
 struct Fl_Fontdesc;
 class Fl_Quartz_Font_Descriptor;
 
@@ -143,30 +133,7 @@ protected:
   void set_fontname_in_fontdesc(Fl_Fontdesc *f);
   void uncache_pixmap(fl_uintptr_t p) FL_OVERRIDE;
 
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  enum {use_CoreText = 1, use_ATSU};
-  static int CoreText_or_ATSU;
-  static void init_CoreText_or_ATSU();
-  void draw_CoreText(const char *str, int n, float x, float y);
-  double width_CoreText(const UniChar* txt, int n);
-  void descriptor_init_CoreText(const char* name, Fl_Fontsize Size, Fl_Quartz_Font_Descriptor *d);
-  void text_extents_CoreText(const char*, int n, int& dx, int& dy, int& w, int& h);
-  Fl_Font set_fonts_CoreText(const char* xstarname);
-
-  void draw_ATSU(const char *str, int n, float x, float y);
-  double width_ATSU(const UniChar* txt, int n);
-  void descriptor_init_ATSU(const char* name, Fl_Fontsize Size, Fl_Quartz_Font_Descriptor *d);
-  void text_extents_ATSU(const char*, int n, int& dx, int& dy, int& w, int& h);
-  Fl_Font set_fonts_ATSU(const char* xstarname);
-
-  // define 2 kinds of pointers to member function
-  typedef void (Fl_Quartz_Graphics_Driver::*pter_to_draw_member)(const char *str, int n, float x, float y);
-  typedef double (Fl_Quartz_Graphics_Driver::*pter_to_width_member)(const UniChar *str, int n);
-  static pter_to_draw_member CoreText_or_ATSU_draw;
-  static pter_to_width_member CoreText_or_ATSU_width;
-#else
   void descriptor_init(const char* name, Fl_Fontsize Size, Fl_Quartz_Font_Descriptor *d);
-#endif
   void overlay_rect(int x, int y, int w , int h) FL_OVERRIDE;
   float override_scale() FL_OVERRIDE;
   void restore_scale(float) FL_OVERRIDE;
diff --git a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.cxx b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.cxx
index 7ee610d24..21c5eda4c 100644
--- a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.cxx
+++ b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver.cxx
@@ -1,7 +1,7 @@
 //
 // Rectangle drawing routines for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2018 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -22,27 +22,6 @@
 #include <FL/fl_draw.H>
 #include <FL/Fl_Image_Surface.H>
 
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-Fl_Quartz_Graphics_Driver::pter_to_draw_member Fl_Quartz_Graphics_Driver::CoreText_or_ATSU_draw;
-Fl_Quartz_Graphics_Driver::pter_to_width_member Fl_Quartz_Graphics_Driver::CoreText_or_ATSU_width;
-
-int Fl_Quartz_Graphics_Driver::CoreText_or_ATSU = 0;
-
-void Fl_Quartz_Graphics_Driver::init_CoreText_or_ATSU()
-{
-  if (Fl_Darwin_System_Driver::calc_mac_os_version() < 100500) {
-    // before Mac OS 10.5, only ATSU is available
-    CoreText_or_ATSU = use_ATSU;
-    CoreText_or_ATSU_draw = &Fl_Quartz_Graphics_Driver::draw_ATSU;
-    CoreText_or_ATSU_width = &Fl_Quartz_Graphics_Driver::width_ATSU;
-  } else {
-    CoreText_or_ATSU = use_CoreText;
-    CoreText_or_ATSU_draw = &Fl_Quartz_Graphics_Driver::draw_CoreText;
-    CoreText_or_ATSU_width = &Fl_Quartz_Graphics_Driver::width_CoreText;
-  }
-}
-#endif
-
 
 void Fl_Quartz_Graphics_Driver::antialias(int state) {
 }
@@ -58,9 +37,6 @@ Fl_Quartz_Graphics_Driver::Fl_Quartz_Graphics_Driver() : Fl_Graphics_Driver(), g
   quartz_line_pattern = 0;
   quartz_line_pattern_size = 0;
   high_resolution_ = false;
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (!CoreText_or_ATSU) init_CoreText_or_ATSU();
-#endif
 }
 
 char Fl_Quartz_Graphics_Driver::can_do_alpha_blending() {
@@ -91,26 +67,10 @@ CGContextRef fl_mac_gc() { return fl_gc; }
 void Fl_Quartz_Graphics_Driver::copy_offscreen(int x, int y, int w, int h, Fl_Offscreen osrc, int srcx, int srcy) {
   // draw portion srcx,srcy,w,h of osrc to position x,y (top-left) of the graphics driver's surface
   CGContextRef src = (CGContextRef)osrc;
-  void *data = CGBitmapContextGetData(src);
   int sw = (int)CGBitmapContextGetWidth(src);
   int sh = (int)CGBitmapContextGetHeight(src);
   CGImageRef img;
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-  if (fl_mac_os_version >= 100400) img = CGBitmapContextCreateImage(src);  // requires 10.4
-  else
-#endif
-  {
-    CGImageAlphaInfo alpha = CGBitmapContextGetAlphaInfo(src);
-    CGColorSpaceRef lut = CGColorSpaceCreateDeviceRGB();
-    // when output goes to a Quartz printercontext, release of the bitmap must be
-    // delayed after the end of the printed page
-    CFRetain(src);
-    CGDataProviderRef src_bytes = CGDataProviderCreateWithData( src, data, sw*sh*4, bmProviderRelease);
-    img = CGImageCreate( sw, sh, 8, 4*8, 4*sw, lut, alpha,
-                        src_bytes, 0L, false, kCGRenderingIntentDefault);
-    CGDataProviderRelease(src_bytes);
-    CGColorSpaceRelease(lut);
-  }
+  img = CGBitmapContextCreateImage(src);  // requires 10.4
   CGAffineTransform at = CGContextGetCTM(src);
   float s = at.a;
   draw_CGImage(img, x, y, w, h, srcx, srcy, sw/s, sh/s);
diff --git a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver_font.cxx b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver_font.cxx
index a277010e3..d373c1768 100644
--- a/src/drivers/Quartz/Fl_Quartz_Graphics_Driver_font.cxx
+++ b/src/drivers/Quartz/Fl_Quartz_Graphics_Driver_font.cxx
@@ -14,61 +14,6 @@
 //     https://www.fltk.org/bugs.php
 //
 
-/* Implementation of support for two text drawing APIs: Core Text (current) and ATSU (legacy)
-
- The HAS_ATSU macro (defined in Fl_Quartz_Graphics_Driver.H) is true
- if and only if ATSU is available at compile time.
- The condition
-   #if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
- is true if and only if both APIs are available at compile time.
- Depending on what MacOS SDK and what deployment target are used, the code can be
- compiled in 2 ways:
-    1) both APIs are available at compile time and which one is used
-       is determined at runtime,
- or
-    2) only one API is available.
-
- When both APIs are compiled in, the choice of which one is used at runtime is done
- the first time the Fl_Quartz_Graphics_Driver constructor runs, and remains unchanged.
- Core Text is selected if the running Mac OS version is ≥ 10.5.
- The static function init_CoreText_or_ATSU() does this by setting the value
- of the class variable CoreText_or_ATSU to either use_CoreText or use_ATSU.
-
- If both APIs are available, several member functions come in groups of 3.
- For example, functions draw(), draw_CoreText() and draw_ATSU() are defined. The only
- task of draw() is to call either draw_CoreText() or draw_ATSU() depending on
- what API has been selected at program start.
-
- If the compilation condition authorizes a single API, one member function
- is defined instead of 3 in the other case. For example, a single draw() function
- is compiled, and contains the same code as what is called either draw_CoreText()
- or draw_ATSU() in the other case.
-
- The ADD_SUFFIX(name, suffix) macro is used so that each function has the
- short (e.g., draw) or long (e.g., draw_CoreText) name adequate for
- each compilation condition.
-
- The 2 most often used text functions are draw() and width(). Two pointers to member
- function are defined. Function init_CoreText_or_ATSU() assigns one with either
- draw_CoreText() or draw_ATSU(), and the other with either width_CoreText() or width_ATSU().
- The draw() and width() functions only have to dereference one pointer to member
- function to call the adequate code.
-
- If the compilation condition authorizes a single text API, only the code related
- to this API (say, CoreText) is compiled whereas all code related to the other API
- (thus, ATSU) is excluded from compilation. Furthermore, none of the code to
- choose API at runtime and to select which member function is called is compiled.
- Consequently, no pointer to member function is used.
-
- The condition for both APIs to be compiled-in is
- - target i386 or ppc architectures
- and
- - use SDK ≥ 10.5 and < 10.11
- and
- - set MacOS deployment target < 10.5 (through the -mmacosx-version-min= compilation option)
-
- */
-
 #include "Fl_Quartz_Graphics_Driver.H"
 #include "Fl_Font.H"
 #include <math.h>
@@ -87,13 +32,6 @@ static CGAffineTransform font_mx = { 1, 0, 0, -1, 0, 0 };
 
 static int fl_free_font = FL_FREE_FONT;
 
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-#  define ADD_SUFFIX(name, suffix) name##suffix
-#else
-#  define ADD_SUFFIX(name, suffix) name
-#endif
-
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 
 static CFMutableDictionaryRef attributes = NULL;
 
@@ -115,28 +53,7 @@ static Fl_Fontdesc built_in_table_PS[] = { // PostScript font names preferred wh
   {"AndaleMono"}, // there is no bold Monaco font on standard Mac
   {"ZapfDingbatsITC"}
 };
-#endif
 
-#if HAS_ATSU
-static Fl_Fontdesc built_in_table_full[] = { // full font names used before 10.5
-  {"Arial"},
-  {"Arial Bold"},
-  {"Arial Italic"},
-  {"Arial Bold Italic"},
-  {"Courier"},
-  {"Courier Bold"},
-  {"Courier New Italic"},
-  {"Courier New Bold Italic"},
-  {"Times New Roman"},
-  {"Times New Roman Bold"},
-  {"Times New Roman Italic"},
-  {"Times New Roman Bold Italic"},
-  {"Symbol"},
-  {"Monaco"},
-  {"Andale Mono"}, // there is no bold Monaco font on standard Mac
-  {"Webdings"}
-};
-#endif
 
 // Bug: older versions calculated the value for *ap as a side effect of
 // making the name, and then forgot about it. To avoid having to change
@@ -178,22 +95,9 @@ int Fl_Quartz_Graphics_Driver::get_font_sizes(Fl_Font fnum, int*& sizep) {
 }
 
 Fl_Quartz_Font_Descriptor::Fl_Quartz_Font_Descriptor(const char* name, Fl_Fontsize Size) : Fl_Font_Descriptor(name, Size) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   fontref = NULL;
-#endif
-#if HAS_ATSU
-  layout = NULL;
-#endif
   Fl_Quartz_Graphics_Driver *driver = (Fl_Quartz_Graphics_Driver*)&Fl_Graphics_Driver::default_driver();
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (Fl_Quartz_Graphics_Driver::CoreText_or_ATSU == Fl_Quartz_Graphics_Driver::use_ATSU) {
-      driver->descriptor_init_ATSU(name, size, this);
-      return;
-    }
-    driver->descriptor_init_CoreText(name, size, this);
-#else
   driver->descriptor_init(name, size, this);
-#endif
 }
 
 
@@ -207,20 +111,12 @@ Fl_Quartz_Font_Descriptor::~Fl_Quartz_Font_Descriptor() {
 #endif
   */
   if (this == fl_graphics_driver->font_descriptor()) fl_graphics_driver->font_descriptor(NULL);
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   if (fontref) {
     CFRelease(fontref);
     for (unsigned i = 0; i < sizeof(width)/sizeof(float*); i++) {
       if (width[i]) free(width[i]);
     }
   }
-#endif
-#if HAS_ATSU
-  if (layout) {
-    ATSUDisposeTextLayout(layout);
-    ATSUDisposeStyle(style);
-  }
-#endif
 }
 
 
@@ -332,9 +228,7 @@ double Fl_Quartz_Graphics_Driver::width(unsigned int wc) {
   return width(utf16, l);
 }
 
-
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-static void set_fontname_CoreText(Fl_Fontdesc *f) {
+void Fl_Quartz_Graphics_Driver::set_fontname_in_fontdesc(Fl_Fontdesc *f) {
   CFStringRef cfname = CFStringCreateWithCString(NULL, f->name, kCFStringEncodingUTF8);
   CTFontRef ctfont = cfname ? CTFontCreateWithName(cfname, 0, NULL) : NULL;
   if (cfname) { CFRelease(cfname); cfname = NULL; }
@@ -348,20 +242,6 @@ static void set_fontname_CoreText(Fl_Fontdesc *f) {
   }
   if (!cfname) strlcpy(f->fontname, f->name, ENDOFBUFFER);
 }
-#endif
-
-void Fl_Quartz_Graphics_Driver::set_fontname_in_fontdesc(Fl_Fontdesc *f) {
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (CoreText_or_ATSU == use_ATSU)
-    strlcpy(f->fontname, f->name, ENDOFBUFFER);
-  else
-    set_fontname_CoreText(f);
-#elif HAS_ATSU
-  strlcpy(f->fontname, f->name, ENDOFBUFFER);
-#else
-  set_fontname_CoreText(f);
-#endif
-}
 
 const char *Fl_Quartz_Graphics_Driver::font_name(int num) {
   if (!fl_fonts) fl_fonts = calc_fl_fonts();
@@ -385,49 +265,11 @@ void Fl_Quartz_Graphics_Driver::font_name(int num, const char *name) {
 
 Fl_Fontdesc* Fl_Quartz_Graphics_Driver::calc_fl_fonts(void)
 {
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-  if (CoreText_or_ATSU == use_ATSU) return built_in_table_full;
   return  built_in_table_PS;
-#elif HAS_ATSU
-  return built_in_table_full;
-#else
-  return  built_in_table_PS;
-#endif
 }
 
 
-#if HAS_ATSU && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-
-void Fl_Quartz_Graphics_Driver::draw(const char *str, int n, float x, float y) {
-  (this->*CoreText_or_ATSU_draw)(str, n, x, y);
-}
-
-double Fl_Quartz_Graphics_Driver::width(const UniChar* txt, int n) {
-  return (this->*CoreText_or_ATSU_width)(txt, n);
-}
-
-Fl_Font Fl_Quartz_Graphics_Driver::set_fonts(const char* xstarname)
-{
-  if (CoreText_or_ATSU == use_ATSU) return set_fonts_ATSU(xstarname);
-  return  set_fonts_CoreText(xstarname);
-}
-
-void Fl_Quartz_Graphics_Driver::text_extents(const char* txt, int n, int& dx, int& dy, int& w, int& h)
-{
-  if (CoreText_or_ATSU == use_ATSU) {
-    text_extents_ATSU(txt, n, dx, dy, w, h);
-    return;
-  }
-  text_extents_CoreText(txt, n, dx, dy, w, h);
-}
-
-#endif
-
-
-/// CoreText-based code
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
-
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(descriptor_init, _CoreText)(const char* name,
+void Fl_Quartz_Graphics_Driver::descriptor_init(const char* name,
                                                       Fl_Fontsize size, Fl_Quartz_Font_Descriptor *d)
 {
   CFStringRef str = CFStringCreateWithCString(NULL, name, kCFStringEncodingUTF8);
@@ -510,7 +352,7 @@ static CGFloat variation_selector_width(CFStringRef str16, Fl_Quartz_Font_Descri
   return retval;
 }
 
-double Fl_Quartz_Graphics_Driver::ADD_SUFFIX(width, _CoreText)(const UniChar* txt, int n)
+double Fl_Quartz_Graphics_Driver::width(const UniChar* txt, int n)
 {
   double retval = 0;
   UniChar uni;
@@ -581,7 +423,7 @@ double Fl_Quartz_Graphics_Driver::ADD_SUFFIX(width, _CoreText)(const UniChar* tx
 
 
 // text extent calculation
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(text_extents, _CoreText)(const char *str8, int n,
+void Fl_Quartz_Graphics_Driver::text_extents(const char *str8, int n,
                                                                     int &dx, int &dy, int &w, int &h) {
   Fl_Quartz_Font_Descriptor *fl_fontsize = valid_font_descriptor();
   UniChar *txt = mac_Utf8_to_Utf16(str8, n, &n);
@@ -615,7 +457,7 @@ static CGColorRef flcolortocgcolor(Fl_Color i)
   return CGColorCreate(cspace, components);
 }
 
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(draw, _CoreText)(const char *str, int n, float x, float y)
+void Fl_Quartz_Graphics_Driver::draw(const char *str, int n, float x, float y)
 {
   Fl_Quartz_Font_Descriptor *fl_fontsize = valid_font_descriptor();
   // convert to UTF-16 first
@@ -680,7 +522,7 @@ static int name_compare(const void *a, const void *b)
   }
 }
 
-Fl_Font Fl_Quartz_Graphics_Driver::ADD_SUFFIX(set_fonts, _CoreText)(const char* xstarname)
+Fl_Font Fl_Quartz_Graphics_Driver::set_fonts(const char* xstarname)
 {
 #pragma unused ( xstarname )
   if (fl_free_font > FL_FREE_FONT) return (Fl_Font)fl_free_font; // if already called
@@ -717,187 +559,3 @@ Fl_Font Fl_Quartz_Graphics_Driver::ADD_SUFFIX(set_fonts, _CoreText)(const char*
   delete[] tabfontnames;
   return (Fl_Font)fl_free_font;
 }
-
-
-#endif // >= 10.5
-
-
-
-/// ATSU-based code to support Mac OS < 10.5
-#if HAS_ATSU
-
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(descriptor_init, _ATSU)(const char* name,
-                                                      Fl_Fontsize size, Fl_Quartz_Font_Descriptor *d)
-{
-  OSStatus err;
-  // fill our structure with a few default values
-  d->ascent = size*3/4.;
-  d->descent = size-d->ascent;
-  d->q_width = size*2/3.;
-  // now we allocate everything needed to render text in this font later
-  // get us the default layout and style
-  err = ATSUCreateTextLayout(&d->layout);
-  UniChar mTxt[2] = { 65, 0 };
-  err = ATSUSetTextPointerLocation(d->layout, mTxt, kATSUFromTextBeginning, 1, 1);
-  err = ATSUCreateStyle(&d->style);
-  err = ATSUSetRunStyle(d->layout, d->style, kATSUFromTextBeginning, kATSUToTextEnd);
-  // now set the actual font, size and attributes. We also set the font matrix to
-  // render our font up-side-down, so when rendered through our inverted CGContext,
-  // text will appear normal again.
-  Fixed fsize = IntToFixed(size);
-  ATSUFontID fontID;
-  ATSUFindFontFromName(name, strlen(name), kFontFullName, kFontMacintoshPlatform, kFontNoScriptCode, kFontEnglishLanguage, &fontID);
-
-  // draw the font upside-down... Compensate for fltk/OSX origin differences
-  ATSUAttributeTag sTag[] = { kATSUFontTag, kATSUSizeTag, kATSUFontMatrixTag };
-  ByteCount sBytes[] = { sizeof(ATSUFontID), sizeof(Fixed), sizeof(CGAffineTransform) };
-  ATSUAttributeValuePtr sAttr[] = { &fontID, &fsize, &font_mx };
-  if (fontID != kATSUInvalidFontID) err = ATSUSetAttributes(d->style, 1, sTag, sBytes, sAttr); // set the font attribute
-  err = ATSUSetAttributes(d->style, 2, sTag + 1, sBytes + 1, sAttr + 1); // then the size and matrix attributes
-  // next, make sure that Quartz will only render at integer coordinates
-  ATSLineLayoutOptions llo = kATSLineUseDeviceMetrics | kATSLineDisableAllLayoutOperations;
-  ATSUAttributeTag aTag[] = { kATSULineLayoutOptionsTag };
-  ByteCount aBytes[] = { sizeof(ATSLineLayoutOptions) };
-  ATSUAttributeValuePtr aAttr[] = { &llo };
-  err = ATSUSetLineControls (d->layout, kATSUFromTextBeginning, 1, aTag, aBytes, aAttr);
-  // now we are finally ready to measure some letter to get the bounding box
-  Fixed bBefore, bAfter, bAscent, bDescent;
-  err = ATSUGetUnjustifiedBounds(d->layout, kATSUFromTextBeginning, 1, &bBefore, &bAfter, &bAscent, &bDescent);
-  // Requesting a certain height font on Mac does not guarantee that ascent+descent
-  // equal the requested height. fl_height will reflect the actual height that we got.
-  // The font "Apple Chancery" is a pretty extreme example of overlapping letters.
-  float fa = -FixedToFloat(bAscent), fd = -FixedToFloat(bDescent);
-  if (fa>0.0f && fd>0.0f) {
-    //float f = Size/(fa+fd);
-    d->ascent = int(fa); //int(fa*f+0.5f);
-    d->descent = int(fd); //Size - ascent;
-  }
-  int w = FixedToInt(bAfter);
-  if (w)
-    d->q_width = FixedToInt(bAfter);
-
-  // Now, by way of experiment, try enabling Transient Font Matching, this will
-  // cause ATSU to find a suitable font to render any chars the current font can't do...
-  ATSUSetTransientFontMatching (d->layout, true);
-}
-
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(draw, _ATSU)(const char *str, int n, float x, float y)
-{
-  Fl_Quartz_Font_Descriptor *fl_fontsize = valid_font_descriptor();
-  // convert to UTF-16 first
-  UniChar *uniStr = mac_Utf8_to_Utf16(str, n, &n);
-  CGContextRef gc = (CGContextRef)this->gc();
-  OSStatus err;
-  // now collect our ATSU resources
-  ATSUTextLayout layout = fl_fontsize->layout;
-
-  ByteCount iSize = sizeof(CGContextRef);
-  ATSUAttributeTag iTag = kATSUCGContextTag;
-  ATSUAttributeValuePtr iValuePtr=&gc;
-  ATSUSetLayoutControls(layout, 1, &iTag, &iSize, &iValuePtr);
-
-  err = ATSUSetTextPointerLocation(layout, uniStr, kATSUFromTextBeginning, n, n);
-  CGContextSetShouldAntialias(gc, true);
-  err = ATSUDrawText(layout, kATSUFromTextBeginning, n, FloatToFixed(x), FloatToFixed(y));
-  CGContextSetShouldAntialias(gc, false);
-}
-
-double Fl_Quartz_Graphics_Driver::ADD_SUFFIX(width, _ATSU)(const UniChar* txt, int n) {
-  OSStatus err;
-  Fixed bBefore, bAfter, bAscent, bDescent;
-  ATSUTextLayout layout;
-  ByteCount iSize;
-  ATSUAttributeTag iTag;
-  ATSUAttributeValuePtr iValuePtr;
-
-  Fl_Quartz_Font_Descriptor *fl_fontsize = valid_font_descriptor();
-  // Here's my ATSU text measuring attempt... This seems to do the Right Thing
-  // now collect our ATSU resources and measure our text string
-  layout = fl_fontsize->layout;
-  // activate the current GC
-  iSize = sizeof(CGContextRef);
-  iTag = kATSUCGContextTag;
-  CGContextRef value = (CGContextRef)fl_graphics_driver->gc();
-  iValuePtr = &value;
-  ATSUSetLayoutControls(layout, 1, &iTag, &iSize, &iValuePtr);
-  // now measure the bounding box
-  err = ATSUSetTextPointerLocation(layout, txt, kATSUFromTextBeginning, n, n);
-  err = ATSUGetUnjustifiedBounds(layout, kATSUFromTextBeginning, n, &bBefore, &bAfter, &bAscent, &bDescent);
-  // If err is OK then return length, else return 0. Or something...
-  int len = FixedToInt(bAfter);
-  return len;
-}
-
-void Fl_Quartz_Graphics_Driver::ADD_SUFFIX(text_extents, _ATSU)(const char *str8, int n,
-                                                                int &dx, int &dy, int &w, int &h)
-{
-  Fl_Quartz_Font_Descriptor *fl_fontsize = valid_font_descriptor();
-  UniChar *txt = mac_Utf8_to_Utf16(str8, n, &n);
-  OSStatus err;
-  ATSUTextLayout layout;
-  ByteCount iSize;
-  ATSUAttributeTag iTag;
-  ATSUAttributeValuePtr iValuePtr;
-
-  // Here's my ATSU text measuring attempt... This seems to do the Right Thing
-  // now collect our ATSU resources and measure our text string
-  layout = fl_fontsize->layout;
-  // activate the current GC
-  iSize = sizeof(CGContextRef);
-  iTag = kATSUCGContextTag;
-  CGContextRef value = (CGContextRef)gc();
-  iValuePtr = &value;
-  ATSUSetLayoutControls(layout, 1, &iTag, &iSize, &iValuePtr);
-  // now measure the bounding box
-  err = ATSUSetTextPointerLocation(layout, txt, kATSUFromTextBeginning, n, n);
-  Rect bbox;
-  err = ATSUMeasureTextImage(layout, kATSUFromTextBeginning, n, 0, 0, &bbox);
-  w = bbox.right - bbox.left;
-  h = bbox.bottom - bbox.top;
-  dx = bbox.left;
-  dy = -bbox.bottom;
-  //printf("r: %d l: %d t: %d b: %d w: %d h: %d\n", bbox.right, bbox.left, bbox.top, bbox.bottom, w, h);
-}
-
-Fl_Font Fl_Quartz_Graphics_Driver::ADD_SUFFIX(set_fonts, _ATSU)(const char* xstarname)
-{
-#pragma unused ( xstarname )
-  if (fl_free_font > FL_FREE_FONT) return (Fl_Font)fl_free_font; // if already called
-
-  ItemCount oFontCount, oCountAgain;
-  ATSUFontID *oFontIDs;
-  // How many fonts?
-  ATSUFontCount (&oFontCount);
-  // now allocate space for them...
-  oFontIDs = (ATSUFontID *)malloc((oFontCount+1) * sizeof(ATSUFontID));
-  ATSUGetFontIDs (oFontIDs, oFontCount, &oCountAgain);
-  // Now oFontIDs should contain a list of all the available Unicode fonts
-  // Iterate through the list to get each font name
-  for (ItemCount idx = 0; idx < oFontCount; idx++)
-  {
-    //  ByteCount actualLength = 0;
-    //  Ptr oName;
-    // How to get the name - Apples docs say call this twice, once to get the length, then again
-    // to get the actual name...
-    //    ATSUFindFontName (oFontIDs[idx], kFontFullName, kFontMacintoshPlatform, kFontRomanScript, kFontEnglishLanguage,
-    //                      0, NULL, &actualLength, NULL);
-    // Now actualLength tells us the length of buffer we need
-    //  oName = (Ptr)malloc(actualLength + 8);
-    // But who's got time for that nonsense? Let's just hard code a fixed buffer (urgh!)
-    ByteCount actualLength = 511;
-    char oName[512];
-    ATSUFindFontName (oFontIDs[idx], kFontFullName, kFontMacintoshPlatform, kFontRomanScript, kFontEnglishLanguage,
-                      actualLength, oName, &actualLength, &oCountAgain);
-    // bounds check and terminate the returned name
-    if(actualLength > 511)
-      oName[511] = 0;
-    else
-      oName[actualLength] = 0;
-    Fl::set_font((Fl_Font)(fl_free_font++), fl_strdup(oName));
-    //  free(oName);
-  }
-  free(oFontIDs);
-  return (Fl_Font)fl_free_font;
-}
-
-#endif // HAS_ATSU
diff --git a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.H b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.H
index 69e00dfd0..3849ea4df 100644
--- a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.H
+++ b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.H
@@ -1,7 +1,7 @@
 //
 // Draw-to-image code for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2021 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -22,10 +22,8 @@
 
 class Fl_Quartz_Image_Surface_Driver : public Fl_Image_Surface_Driver {
 private:
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   CGImageRef mask_;
   void mask(const Fl_RGB_Image *) FL_OVERRIDE;
-#endif
   void end_current() FL_OVERRIDE;
 public:
   FLWindow *pre_window;
diff --git a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
index 1e3d6b927..4615ba475 100644
--- a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
+++ b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
@@ -1,7 +1,7 @@
 //
 // Draw-to-image code for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2023 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -23,9 +23,7 @@
 
 
 Fl_Quartz_Image_Surface_Driver::Fl_Quartz_Image_Surface_Driver(int w, int h, int high_res, Fl_Offscreen off) : Fl_Image_Surface_Driver(w, h, high_res, off) {
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   mask_ = NULL;
-#endif
   int W = w, H = h;
   float s = 1;
   if (high_res) {
@@ -53,11 +51,9 @@ Fl_Quartz_Image_Surface_Driver::Fl_Quartz_Image_Surface_Driver(int w, int h, int
 }
 
 Fl_Quartz_Image_Surface_Driver::~Fl_Quartz_Image_Surface_Driver() {
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (mask_) {
     CGImageRelease(mask_);
   }
-#endif
   if (offscreen) CGContextRestoreGState((CGContextRef)offscreen);
   if (offscreen && !external_offscreen) {
     void *data = CGBitmapContextGetData((CGContextRef)offscreen);
@@ -74,7 +70,6 @@ void Fl_Quartz_Image_Surface_Driver::set_current() {
   driver()->gc((CGContextRef)offscreen);
   fl_window = 0;
   ((Fl_Quartz_Graphics_Driver*)driver())->high_resolution( CGBitmapContextGetWidth((CGContextRef)offscreen) > (size_t)width );
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (mask_) {
     int W, H;
     printable_rect(&W, &H);
@@ -82,7 +77,6 @@ void Fl_Quartz_Image_Surface_Driver::set_current() {
     CGContextClipToMask((CGContextRef)offscreen, CGRectMake(0,0,W,H), mask_); // 10.4
     CGContextSaveGState((CGContextRef)offscreen);
   }
-# endif
 }
 
 void Fl_Quartz_Image_Surface_Driver::translate(int x, int y) {
@@ -99,13 +93,11 @@ void Fl_Quartz_Image_Surface_Driver::untranslate() {
 Fl_RGB_Image* Fl_Quartz_Image_Surface_Driver::image()
 {
   CGContextFlush((CGContextRef)offscreen);
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (mask_) {
     CGContextRestoreGState((CGContextRef)offscreen);
     CGImageRelease(mask_);
     mask_ = NULL;
   }
-#endif
   int W = (int)CGBitmapContextGetWidth((CGContextRef)offscreen);
   int H = (int)CGBitmapContextGetHeight((CGContextRef)offscreen);
   int bpr = (int)CGBitmapContextGetBytesPerRow((CGContextRef)offscreen);
@@ -128,19 +120,15 @@ Fl_RGB_Image* Fl_Quartz_Image_Surface_Driver::image()
 
 void Fl_Quartz_Image_Surface_Driver::end_current()
 {
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
   if (mask_) {
     CGContextRestoreGState((CGContextRef)offscreen);
     CGContextRestoreGState((CGContextRef)offscreen);
   }
-# endif
   fl_window = pre_window;
   Fl_Surface_Device::end_current();
 }
 
 
-# if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
-
 static void MyProviderReleaseData (void *info, const void *data, size_t size) {
   delete[] (uchar*)data;
 }
@@ -177,5 +165,3 @@ void Fl_Quartz_Image_Surface_Driver::mask(const Fl_RGB_Image *img) {
   CFRelease(provider);
   if (using_copy) delete img;
 }
-
-#endif
diff --git a/test/blocks.cxx b/test/blocks.cxx
index b2ab76435..8b943b734 100644
--- a/test/blocks.cxx
+++ b/test/blocks.cxx
@@ -1,7 +1,7 @@
 //
 // "Block Attack!" scrolling blocks game using the Fast Light Tool Kit (FLTK).
 //
-// Copyright © 2006-2021 by Michael Sweet.
+// Copyright © 2006-2026 by Michael Sweet.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -150,12 +150,7 @@ class BlockSound {
   // Private, OS-specific data...
 #ifdef __APPLE__
   AudioDeviceID device;
-#ifndef MAC_OS_X_VERSION_10_5
-#define MAC_OS_X_VERSION_10_5 1050
-#endif
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   AudioDeviceIOProcID audio_proc_id;
-#  endif
   AudioStreamBasicDescription format;
   short *data;
   int remaining;
@@ -225,13 +220,8 @@ BlockSound::BlockSound() {
   if (format.mFormatID != kAudioFormatLinearPCM) return;
 
   // Attach the callback and start the device
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   if (AudioDeviceCreateIOProcID(device, audio_cb, (void *)this, &audio_proc_id) != noErr) return;
   AudioDeviceStart(device, audio_proc_id);
-#  else
-  if (AudioDeviceAddIOProc(device, audio_cb, (void *)this) != noErr) return;
-  AudioDeviceStart(device, audio_cb);
-#  endif
 
   sample_size = (int)format.mSampleRate;
 
@@ -323,13 +313,8 @@ BlockSound::BlockSound() {
 BlockSound::~BlockSound() {
 #ifdef __APPLE__
   if (sample_size) {
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
     AudioDeviceStop(device, audio_proc_id);
     AudioDeviceDestroyIOProcID(device, audio_proc_id);
-#  else
-    AudioDeviceStop(device, audio_cb);
-    AudioDeviceRemoveIOProc(device, audio_cb);
-#  endif
   }
 
 #elif defined(_WIN32)
diff --git a/test/sudoku.cxx b/test/sudoku.cxx
index c0d6bfd43..f6e78c170 100644
--- a/test/sudoku.cxx
+++ b/test/sudoku.cxx
@@ -2,7 +2,7 @@
 // Sudoku game using the Fast Light Tool Kit (FLTK).
 //
 // Copyright 2005-2018 by Michael Sweet.
-// Copyright 2019-2021 by Bill Spitzak and others.
+// Copyright 2019-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -90,9 +90,7 @@ class SudokuSound {
   // Private, OS-specific data...
 #ifdef __APPLE__
   AudioDeviceID device;
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   AudioDeviceIOProcID audio_proc_id;
-#  endif
   AudioStreamBasicDescription format;
   short *data;
   int remaining;
@@ -263,13 +261,8 @@ SudokuSound::SudokuSound() {
   if (format.mFormatID != kAudioFormatLinearPCM) return;
 
   // Attach the callback and start the device
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
   if (AudioDeviceCreateIOProcID(device, audio_cb, (void *)this, &audio_proc_id) != noErr) return;
   AudioDeviceStart(device, audio_proc_id);
-#  else
-  if (AudioDeviceAddIOProc(device, audio_cb, (void *)this) != noErr) return;
-  AudioDeviceStart(device, audio_cb);
-#  endif
 
   sample_size = (int)format.mSampleRate / 20;
 
@@ -369,13 +362,8 @@ SudokuSound::SudokuSound() {
 SudokuSound::~SudokuSound() {
 #ifdef __APPLE__
   if (sample_size) {
-#  if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
     AudioDeviceStop(device, audio_proc_id);
     AudioDeviceDestroyIOProcID(device, audio_proc_id);
-#  else
-    AudioDeviceStop(device, audio_cb);
-    AudioDeviceRemoveIOProc(device, audio_cb);
-#  endif
   }
 
 #elif defined(_WIN32)