diff --git a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
index 33d7dcbcf4..0274ed8201 100644
--- a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
+++ b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
@@ -163,6 +163,7 @@ public:
     // The following variables help organizing modal sessions:
     QStack<QCocoaModalSessionInfo> cocoaModalSessionStack;
     bool currentExecIsNSAppRun;
+    bool modalSessionOnNSAppRun;
     bool nsAppRunCalledByQt;
     bool cleanupModalSessionsNeeded;
     uint processEventsCalled;
diff --git a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
index 91b631bff9..495a54cac4 100644
--- a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
+++ b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
@@ -721,7 +721,6 @@ void QCocoaEventDispatcherPrivate::beginModalSession(QWindow *window)
     // setting currentModalSessionCached to zero, so that interrupt() calls
     // [NSApp abortModal] if another modal session is currently running
     Q_Q(QCocoaEventDispatcher);
-    q->interrupt();
 
     // Add a new, empty (null), NSModalSession to the stack.
     // It will become active the next time QEventDispatcher::processEvents is called.
@@ -734,6 +733,12 @@ void QCocoaEventDispatcherPrivate::beginModalSession(QWindow *window)
     cocoaModalSessionStack.push(info);
     updateChildrenWorksWhenModal();
     currentModalSessionCached = 0;
+    if (currentExecIsNSAppRun) {
+        modalSessionOnNSAppRun = true;
+        q->wakeUp();
+    } else {
+        q->interrupt();
+    }
 }
 
 void QCocoaEventDispatcherPrivate::endModalSession(QWindow *window)
@@ -772,6 +777,7 @@ QCocoaEventDispatcherPrivate::QCocoaEventDispatcherPrivate()
       runLoopTimerRef(0),
       blockSendPostedEvents(false),
       currentExecIsNSAppRun(false),
+      modalSessionOnNSAppRun(false),
       nsAppRunCalledByQt(false),
       cleanupModalSessionsNeeded(false),
       processEventsCalled(0),
@@ -902,6 +908,14 @@ void QCocoaEventDispatcherPrivate::postedEventsSourceCallback(void *info)
         // processEvents() was called "manually," ignore this source for now
         d->maybeCancelWaitForMoreEvents();
         return;
+    } else if (d->modalSessionOnNSAppRun) {
+        // We're about to spawn the 1st modal session on top of the main runloop.
+        // Instead of calling processPostedEvents(), which would need us stop
+        // NSApp, we just re-enter processEvents(). This is equivalent to calling
+        // QDialog::exec() except that it's done in a non-blocking way.
+        d->modalSessionOnNSAppRun = false;
+        d->q_func()->processEvents(QEventLoop::DialogExec | QEventLoop::EventLoopExec | QEventLoop::WaitForMoreEvents);
+        return;
     }
     d->processPostedEvents();
     d->maybeCancelWaitForMoreEvents();