diff --git a/.tmux.conf b/.tmux.conf
index 163eaf1..e69fab4 100644
--- a/.tmux.conf
+++ b/.tmux.conf
@@ -177,6 +177,14 @@ run 'cut -c3- ~/.tmux.conf | sh -s _apply_configuration'
 #
 # export LC_NUMERIC=C
 #
+# if ! printf '' | sed -E 's///' 2>/dev/null; then
+#   if printf '' | sed -r 's///' 2>/dev/null; then
+#     sed () {
+#       command sed "${@/-E/-r}"
+#     }
+#   fi
+# fi
+#
 # __newline='
 # '
 #