diff --git a/src/edit.c b/src/edit.c
index fb347b8..9caca85 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -8597,7 +8597,12 @@
     tpos = curwin->w_cursor;
     if (oneleft() == OK)
     {
-	start_arrow(&tpos);
+#if defined(FEAT_XIM) && defined(FEAT_GUI_GTK)
+	/* Only call start_arrow() when not busy with preediting, it will
+	 * break undo.  K_LEFT is inserted in im_correct_cursor(). */
+	if (!im_is_preediting())
+#endif
+	    start_arrow(&tpos);
 #ifdef FEAT_RIGHTLEFT
 	/* If exit reversed string, position is fixed */
 	if (revins_scol != -1 && (int)curwin->w_cursor.col >= revins_scol)
diff --git a/src/mbyte.c b/src/mbyte.c
index bcfca82..92f00e0 100644
--- a/src/mbyte.c
+++ b/src/mbyte.c
@@ -3514,6 +3514,11 @@
 	add_to_input_buf(delkey, (int)sizeof(delkey));
 }
 
+/*
+ * Move the cursor left by "num_move_back" characters.
+ * Note that ins_left() checks im_is_preediting() to avoid breaking undo for
+ * these K_LEFT keys.
+ */
     static void
 im_correct_cursor(int num_move_back)
 {
@@ -3741,8 +3746,7 @@
     }
     else if (cursor_index == 0 && preedit_string[0] == '\0')
     {
-	if (preedit_start_col == MAXCOL)
-	    xim_has_preediting = FALSE;
+	xim_has_preediting = FALSE;
 
 	/* If at the start position (after typing backspace)
 	 * preedit_start_col must be reset. */
diff --git a/src/version.c b/src/version.c
index 3c2d9a3..1429289 100644
--- a/src/version.c
+++ b/src/version.c
@@ -667,6 +667,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    67,
+/**/
     66,
 /**/
     65,