diff --git a/kitty/rc/close_tab.py b/kitty/rc/close_tab.py
index c45d2991c..c4315b248 100644
--- a/kitty/rc/close_tab.py
+++ b/kitty/rc/close_tab.py
@@ -54,7 +54,7 @@ Do not return an error if no tabs are matched to be closed.
             if payload_get('ignore_no_match'):
                 return None
             raise
-        for tab in tabs:
+        for tab in tuple(tabs):
             if tab:
                 boss.close_tab_no_confirm(tab)
         return None
diff --git a/kitty/rc/close_window.py b/kitty/rc/close_window.py
index dd99e2127..b854335c5 100644
--- a/kitty/rc/close_window.py
+++ b/kitty/rc/close_window.py
@@ -46,7 +46,7 @@ Do not return an error if no windows are matched to be closed.
             if payload_get('ignore_no_match'):
                 return None
             raise
-        for window in windows:
+        for window in tuple(windows):
             if window:
                 boss.mark_window_for_close(window)
         return None