commit https://github.com/vim/vim/commit/e7d1376b636e6c758196c3542bd2c1053f9edb75 Author: Bram Moolenaar <Bram@vim.org> Date: Fri Oct 30 14:23:33 2015 +0100 patch 7.4.901 Problem: When a BufLeave autocommand changes folding in a way it syncs undo, undo can be corrupted. Solution: Prevent undo sync. (Jacob Niehus)

--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    901,
+/**/
     900,
 /**/
     899,