diff --git a/kitty/mouse.c b/kitty/mouse.c
index a0b6361e0..97c84b961 100644
--- a/kitty/mouse.c
+++ b/kitty/mouse.c
@@ -143,7 +143,7 @@ encode_mouse_scroll(Window *w, int button, int mods) {
 
 static Window*
 window_for_id(id_type window_id) {
-    if (global_state.callback_os_window && global_state.callback_os_window->tabs) {
+    if (global_state.callback_os_window && global_state.callback_os_window->num_tabs) {
         Tab *t = global_state.callback_os_window->tabs + global_state.callback_os_window->active_tab;
         for (unsigned int i = 0; i < t->num_windows; i++) {
             Window *w = t->windows + i;