From 50b61bef6f41778b0e42796e618820ac228a219a Mon Sep 17 00:00:00 2001
From: Benno Schulenberg <bensberg@telfort.nl>
Date: Sat, 15 Aug 2020 13:44:25 +0200
Subject: [PATCH] input: discard any multibyte character when <Alt> is being
 held

Otherwise the <Alt> key would simply be ignored.  It's better to reject
the combination, to compel the user to be precise in what they type.
---
 src/winio.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/winio.c b/src/winio.c
index afef1d4c..715be3c0 100644
--- a/src/winio.c
+++ b/src/winio.c
@@ -938,6 +938,13 @@ int parse_kbinput(WINDOW *win)
 			else if (keycode == KEY_BACKSPACE || keycode == '\b' ||
 												keycode == DEL_CODE)
 				return CONTROL_SHIFT_DELETE;
+#endif
+#ifdef ENABLE_UTF8
+			else if (0xC0 <= keycode && keycode <= 0xFF && using_utf8()) {
+				while (key_buffer_len > 0 && 0x80 <= *key_buffer && *key_buffer <= 0xBF)
+					get_input(NULL);
+				return FOREIGN_SEQUENCE;
+			}
 #endif
 			else if (!solitary && keycode < 0x20)
 				meta_key = TRUE;