diff --git a/runtime/doc/syntax.txt b/runtime/doc/syntax.txt
index ee8d689..acc4783 100644
--- a/runtime/doc/syntax.txt
+++ b/runtime/doc/syntax.txt
@@ -1,4 +1,4 @@
-*syntax.txt*	For Vim version 9.1.  Last change: 2024 Jul 03
+*syntax.txt*	For Vim version 9.1.  Last change: 2024 Jul 06
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -1221,6 +1221,21 @@
 "filetype_csh" variable exists, the filetype will be set to the value of the
 variable.
 
+CSV							*ft-csv-syntax*
+
+If you change the delimiter of the CSV file, the syntax highlighting will be
+now longer match the changed file content. You will need to unlet the
+following variable: >
+
+	:unlet b:csv_delimiter
+
+And afterwards save and reload the file: >
+
+	:w
+	:e
+
+Now the syntax engine should determine the newly changed csv delimiter.
+
 
 CYNLIB						*cynlib.vim* *ft-cynlib-syntax*