st.c | 4 ++++

diff --git a/st.c b/st.c
index 15d22aca403d6fac06862d491ec8a4fd219df388..f3b0b080b04d1669f776f4eed7f63f7a45d33b7f 100644
--- a/st.c
+++ b/st.c
@@ -1509,6 +1509,9 @@ 			strdump();
 			break;
 		}
 		break;
+	case 'k': /* old title set compatibility */
+		XStoreName(xw.dpy, xw.win, strescseq.buf);
+		break;
 	case 'P': /* DSC -- Device Control String */
 	case '_': /* APC -- Application Program Command */
 	case '^': /* PM -- Privacy Message */
@@ -1624,6 +1627,7 @@ 			case 'P': /* DCS -- Device Control String */
 			case '_': /* APC -- Application Program Command */
 			case '^': /* PM -- Privacy Message */
 			case ']': /* OSC -- Operating System Command */
+			case 'k': /* old title set compatibility */
 				strreset();
 				strescseq.type = ascii;
 				term.esc |= ESC_STR;