updated for version 7.3.859
Problem: 'ambiwidth' must be set by the user.
Solution: Detects East Asian ambiguous width (UAX #11) state of the terminal
at the start-up time and 'ambiwidth' accordingly. (Hayaki Saito)
diff --git a/src/main.c b/src/main.c
index 6581ba9..ef48934 100644
--- a/src/main.c
+++ b/src/main.c
@@ -804,6 +804,9 @@
starttermcap(); /* start termcap if not done by wait_return() */
TIME_MSG("start termcap");
+#if defined(FEAT_TERMRESPONSE) && defined(FEAT_MBYTE)
+ may_req_ambiguous_character_width();
+#endif
#ifdef FEAT_MOUSE
setmouse(); /* may start using the mouse */