Problem:  crash with WinNewPre autocommand

Problem:  crash with WinNewPre autocommand, because window
          structures are not yet safe to use
Solution: Don't trigger WinNewPre on :tabnew

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/autocmd.txt b/runtime/doc/autocmd.txt
index 0461c04..f6d32db 100644
--- a/runtime/doc/autocmd.txt
+++ b/runtime/doc/autocmd.txt
@@ -1,4 +1,4 @@
-*autocmd.txt*   For Vim version 9.1.  Last change: 2024 Jul 17
+*autocmd.txt*   For Vim version 9.1.  Last change: 2024 Aug 10
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1427,8 +1427,10 @@
 							*WinNewPre*
 WinNewPre			Before creating a new window. Triggered
 				before commands that modify window layout by
-				creating a split or new tab page. Not done for
-				the first window, when Vim has just started.
+				creating a split.
+				Not done for creating tabs or for the first
+				window, as the window structure is not
+				initialized yet and so is generally not safe.
 				It is not allowed to modify window layout
 				while executing commands for the WinNewPre
 				event.