patch 8.2.0011: screen updating wrong when opeing preview window

Problem:    Screen updating wrong when opeing preview window.
Solution:   Redraw the window when the preview window opens.
diff --git a/src/version.c b/src/version.c
index eb031ab..c4c583a 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    11,
+/**/
     10,
 /**/
     9,