diff --git a/docs/changelog.rst b/docs/changelog.rst
index 036a722d6..3d9626498 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -18,6 +18,8 @@ Changelog
 - macOS: Ensure that when running from a bundle, the bundle kitty exe is
   preferred over any kitty in PATH (:iss:`1280`)
 
+- macOS: Fix a regression that broke mapping of :kbd:`ctrl+tab` (:iss:`1304`)
+
 - Add a list of user-created kittens to the docs
 
 - Fix a regression that broke changing mouse wheel scroll direction with
diff --git a/glfw/cocoa_init.m b/glfw/cocoa_init.m
index 2d883d084..e567c6736 100644
--- a/glfw/cocoa_init.m
+++ b/glfw/cocoa_init.m
@@ -299,6 +299,14 @@ static GLFWbool initializeTIS(void)
 //////                       GLFW platform API                      //////
 //////////////////////////////////////////////////////////////////////////
 
+static inline bool
+is_ctrl_tab(NSEvent *event) {
+    NSEventModifierFlags modifierFlags = [event modifierFlags] & NSEventModifierFlagDeviceIndependentFlagsMask;
+    return event.keyCode == kVK_Tab && (modifierFlags == NSEventModifierFlagControl || modifierFlags == (
+                NSEventModifierFlagControl | NSEventModifierFlagShift));
+}
+
+
 int _glfwPlatformInit(void)
 {
     _glfw.ns.autoreleasePool = [[NSAutoreleasePool alloc] init];
@@ -312,8 +320,7 @@ int _glfwPlatformInit(void)
 
     NSEvent* (^keydown_block)(NSEvent*) = ^ NSEvent* (NSEvent* event)
     {
-        NSEventModifierFlags modifierFlags = [event modifierFlags];
-        if (event.keyCode == kVK_Tab && (modifierFlags == NSEventModifierFlagControl || modifierFlags == (NSEventModifierFlagControl | NSEventModifierFlagShift))) {
+        if (is_ctrl_tab(event)) {
             // Cocoa swallows Ctrl+Tab to cycle between views
             [[NSApp keyWindow].contentView keyDown:event];
         }
@@ -323,14 +330,13 @@ int _glfwPlatformInit(void)
 
     NSEvent* (^keyup_block)(NSEvent*) = ^ NSEvent* (NSEvent* event)
     {
-        NSEventModifierFlags modifierFlags = [event modifierFlags];
         if ([event modifierFlags] & NSEventModifierFlagCommand) {
             // From http://cocoadev.com/index.pl?GameKeyboardHandlingAlmost
             // This works around an AppKit bug, where key up events while holding
             // down the command key don't get sent to the key window.
             [[NSApp keyWindow] sendEvent:event];
         }
-        if (event.keyCode == kVK_Tab && (modifierFlags == NSEventModifierFlagControl || modifierFlags == (NSEventModifierFlagControl | NSEventModifierFlagShift))) {
+        if (is_ctrl_tab(event)) {
             // Cocoa swallows Ctrl+Tab to cycle between views
             [[NSApp keyWindow].contentView keyUp:event];
         }