updated for version 7.3.801
Problem:    ":window set nu?" displays the cursor line. (Nazri Ramliy)
Solution:   Do not update the cursor line when conceallevel is zero or the
            screen has scrolled. (partly by Christian Brabandt)
diff --git a/src/version.c b/src/version.c
index af8210a..69184b0 100644
--- a/src/version.c
+++ b/src/version.c
@@ -726,6 +726,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    801,
+/**/
     800,
 /**/
     799,
diff --git a/src/window.c b/src/window.c
index b5d4afd..1a09c91 100644
--- a/src/window.c
+++ b/src/window.c
@@ -3991,9 +3991,10 @@
 
 #ifdef FEAT_CONCEAL
     /* Conceal cursor line in previous window, unconceal in current window. */
-    if (win_valid(owp))
+    if (win_valid(owp) && owp->w_p_cole > 0 && !msg_scrolled)
 	update_single_line(owp, owp->w_cursor.lnum);
-    update_single_line(curwin, curwin->w_cursor.lnum);
+    if (curwin->w_p_cole > 0 && !msg_scrolled)
+	need_cursor_line_redraw = TRUE;
 #endif
 }