diff --git a/.tmux.conf b/.tmux.conf
index 4d8b357..f9bd1a9 100644
--- a/.tmux.conf
+++ b/.tmux.conf
@@ -14,6 +14,10 @@ set -g focus-events on
 # eliminate key code delay
 set -s escape-time 0
 
+# extended keys (CSI u / modifyOtherKeys)
+set -g extended-keys on
+set -as terminal-features '*:extkeys'
+
 # Ghostty cursor shape passthrough
 set -ga terminal-overrides ',*:Ss=\E[%p1%d q:Se=\E[2 q',