Update runtime files
diff --git a/runtime/doc/diff.txt b/runtime/doc/diff.txt
index 216922a..3caa7cf 100644
--- a/runtime/doc/diff.txt
+++ b/runtime/doc/diff.txt
@@ -1,4 +1,4 @@
-*diff.txt*      For Vim version 9.0.  Last change: 2023 Jan 21
+*diff.txt*      For Vim version 9.0.  Last change: 2023 Apr 04
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -109,6 +109,7 @@
 		accidentally being patched.  But it may still result in
 		various ".rej" files to be created.  And when absolute path
 		names are present these files may get patched anyway.
+		Using the "patch" command is not allowed in |restricted-mode|.
 
 To make these commands use a vertical split, prepend |:vertical|.  Examples: >