diff --git a/modules/juce_core/native/juce_ObjCHelpers_mac.h b/modules/juce_core/native/juce_ObjCHelpers_mac.h
index 7f2c9c5700..aa4e45d218 100644
--- a/modules/juce_core/native/juce_ObjCHelpers_mac.h
+++ b/modules/juce_core/native/juce_ObjCHelpers_mac.h
@@ -585,6 +585,63 @@ private:
     Class klass = nullptr;
 };
 
+//==============================================================================
+/*
+    Forwards NSNotificationCenter callbacks to a std::function<void()>.
+*/
+class FunctionNotificationCenterObserver
+{
+public:
+    FunctionNotificationCenterObserver (NSNotificationName notificationName,
+                                        id objectToObserve,
+                                        std::function<void()> callback)
+        : onNotification (std::move (callback)),
+          observer (observerObject.get(), getSelector(), notificationName, objectToObserve)
+    {}
+
+private:
+    static SEL getSelector()
+    {
+        JUCE_BEGIN_IGNORE_WARNINGS_GCC_LIKE ("-Wundeclared-selector")
+        return @selector (notificationFired:);
+        JUCE_END_IGNORE_WARNINGS_GCC_LIKE
+    }
+
+    std::function<void()> onNotification;
+
+    NSUniquePtr<NSObject> observerObject
+    {
+        [this]
+        {
+            static auto observerClass = std::invoke ([]
+            {
+                ObjCClass<NSObject> k { "JUCEObserverClass_" };
+
+                k.addIvar<FunctionNotificationCenterObserver*> ("owner");
+
+                k.addMethod (getSelector(), [] (id self, SEL, NSNotification*)
+                {
+                    getIvar<FunctionNotificationCenterObserver*> (self, "owner")->onNotification();
+                });
+
+                k.registerClass();
+
+                return k;
+            });
+            auto* result = observerClass.createInstance();
+            object_setInstanceVariable (result, "owner", this);
+            return result;
+        }()
+    };
+
+    ScopedNotificationCenterObserver observer;
+
+    // Instances can't be copied or moved, because 'this' is stored as a member of the ObserverClass
+    // object.
+    JUCE_DECLARE_NON_COPYABLE (FunctionNotificationCenterObserver)
+    JUCE_DECLARE_NON_MOVEABLE (FunctionNotificationCenterObserver)
+};
+
 #if JUCE_IOS
 
 // Defines a function that will check the requested version both at
diff --git a/modules/juce_gui_basics/native/juce_PerScreenDisplayLinks_mac.h b/modules/juce_gui_basics/native/juce_PerScreenDisplayLinks_mac.h
index dcea884cf9..983a772317 100644
--- a/modules/juce_gui_basics/native/juce_PerScreenDisplayLinks_mac.h
+++ b/modules/juce_gui_basics/native/juce_PerScreenDisplayLinks_mac.h
@@ -35,69 +35,6 @@
 namespace juce
 {
 
-//==============================================================================
-/*
-    Forwards NSNotificationCenter callbacks to a std::function<void()>.
-*/
-class FunctionNotificationCenterObserver
-{
-public:
-    FunctionNotificationCenterObserver (NSNotificationName notificationName,
-                                        id objectToObserve,
-                                        std::function<void()> callback)
-        : onNotification (std::move (callback)),
-          observer (observerObject.get(), getSelector(), notificationName, objectToObserve)
-    {}
-
-private:
-    struct ObserverClass
-    {
-        ObserverClass()
-        {
-            klass.addIvar<FunctionNotificationCenterObserver*> ("owner");
-
-            klass.addMethod (getSelector(), [] (id self, SEL, NSNotification*)
-            {
-                getIvar<FunctionNotificationCenterObserver*> (self, "owner")->onNotification();
-            });
-
-            klass.registerClass();
-        }
-
-        NSObject* createInstance() const { return klass.createInstance(); }
-
-    private:
-        ObjCClass<NSObject> klass { "JUCEObserverClass_" };
-    };
-
-    static SEL getSelector()
-    {
-        JUCE_BEGIN_IGNORE_WARNINGS_GCC_LIKE ("-Wundeclared-selector")
-        return @selector (notificationFired:);
-        JUCE_END_IGNORE_WARNINGS_GCC_LIKE
-    }
-
-    std::function<void()> onNotification;
-
-    NSUniquePtr<NSObject> observerObject
-    {
-        [this]
-        {
-            static ObserverClass observerClass;
-            auto* result = observerClass.createInstance();
-            object_setInstanceVariable (result, "owner", this);
-            return result;
-        }()
-    };
-
-    ScopedNotificationCenterObserver observer;
-
-    // Instances can't be copied or moved, because 'this' is stored as a member of the ObserverClass
-    // object.
-    JUCE_DECLARE_NON_COPYABLE (FunctionNotificationCenterObserver)
-    JUCE_DECLARE_NON_MOVEABLE (FunctionNotificationCenterObserver)
-};
-
 //==============================================================================
 /*
     Manages the lifetime of a CVDisplayLinkRef for a single display, and automatically starts and