Update runtime files
diff --git a/runtime/doc/autocmd.txt b/runtime/doc/autocmd.txt
index 04f0191..a1408ed 100644
--- a/runtime/doc/autocmd.txt
+++ b/runtime/doc/autocmd.txt
@@ -1,4 +1,4 @@
-*autocmd.txt*   For Vim version 9.0.  Last change: 2023 Feb 18
+*autocmd.txt*   For Vim version 9.0.  Last change: 2023 May 20
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1017,6 +1017,9 @@
 				the option. Similarly |v:option_oldglobal| is
 				only set when |:set| or |:setglobal| was used.
 
+				This does not set |<abuf>|, you could use
+				|bufnr()|.
+
 				Note that when setting a |global-local| string
 				option with |:set|, then |v:option_old| is the
 				old global value. However, for all other kinds