diff --git a/packages/coding-agent/docs/tmux.md b/packages/coding-agent/docs/tmux.md
index 091d61647..c781ffe0a 100644
--- a/packages/coding-agent/docs/tmux.md
+++ b/packages/coding-agent/docs/tmux.md
@@ -53,3 +53,7 @@ set -g extended-keys on
 Pi supports the xterm `modifyOtherKeys` format used by these versions. Restart tmux and repeat the verification steps.
 
 For older versions, upgrade tmux or use Pi outside tmux rather than relying on modified Enter shortcuts.
+
+## Color codes appear in the editor with tmux 3.6
+
+If text such as `c0c/0c0c/0c0c` appears in the editor at startup, upgrade tmux to 3.7 or newer. tmux 3.6 sometimes sends the terminal's color replies to Pi as typed text ([tmux#4749](https://github.com/tmux/tmux/issues/4749)). Changing Pi's theme does not help.