From 77ac85f97b24e92f98fb98b1d79887c233ca3cb5 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Tue, 3 Mar 2026 08:51:41 +0530
Subject: [PATCH] macOS: Fix flicker during OS Window resize

Do not sync rendering to system vsync in out of sequence renders.
---
 docs/changelog.rst | 2 ++
 kitty/glfw.c       | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index c402e94a0..679e0bc0d 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -254,6 +254,8 @@ Detailed list of changes
 - macOS: Fix a crash when using :opt:`macos_traditional_fullscreen` with split
   view (:pull:`9573`)
 
+- macOS: Fix flickering during OS Window resize (:disc:`9582`)
+
 
 0.45.0 [2025-12-24]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/kitty/glfw.c b/kitty/glfw.c
index 8c4504fd9..7daa39f3c 100644
--- a/kitty/glfw.c
+++ b/kitty/glfw.c
@@ -361,7 +361,11 @@ cocoa_out_of_sequence_render(OSWindow *window) {
     }
 
     bool rendered = false;
-    if (window->fonts_data->sprite_map) rendered = render_os_window(window, monotonic(), true);
+    if (window->fonts_data->sprite_map) {
+        window->needs_render = true;
+        window->render_state = RENDER_FRAME_READY;
+        rendered = render_os_window(window, monotonic(), true);
+    }
     if (!rendered) {
         debug_rendering("Cocoa out of sequence render did not happen\n");
         blank_os_window(window);