diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 39806015ea..10a06804d3 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt*	For Vim version 9.1.  Last change: 2024 Oct 01
+*options.txt*	For Vim version 9.1.  Last change: 2024 Oct 02
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -3503,14 +3503,14 @@ A jump table for the options with a short description can be found at |Q_op|.
 		/* vim: set filetype=idl : */ ~
 	|FileType| |filetypes|
 	When a dot appears in the value then this separates two filetype
-	names.  Example:
+	names, it should therefore not be used for a filetype.  Example:
 		/* vim: set filetype=c.doxygen : */ ~
 	This will use the "c" filetype first, then the "doxygen" filetype.
 	This works both for filetype plugins and for syntax files.  More than
 	one dot may appear.
 	This option is not copied to another buffer, independent of the 's' or
 	'S' flag in 'cpoptions'.
-	Only normal file name characters can be used, "/\*?[|<>" are illegal.
+	Only alphanumeric characters, '-' and '_' can be used.
 
 						*'fillchars'* *'fcs'*
 'fillchars' 'fcs'	string	(default "vert:|,fold:-,eob:~")
@@ -4992,7 +4992,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	Setting this option to a valid keymap name has the side effect of
 	setting 'iminsert' to one, so that the keymap becomes effective.
 	'imsearch' is also set to one, unless it was -1
-	Only normal file name characters can be used, "/\*?[|<>" are illegal.
+	Only alphanumeric characters, '.', '-' and '_' can be used.
 
 					*'keymodel'* *'km'*
 'keymodel' 'km'		string	(default "")
@@ -8112,7 +8112,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	Syntax autocommand event is triggered with the value as argument.
 	This option is not copied to another buffer, independent of the 's' or
 	'S' flag in 'cpoptions'.
-	Only normal file name characters can be used, "/\*?[|<>" are illegal.
+	Only alphanumeric characters, '.', '-' and '_' can be used.
 
 						*'tabclose'* *'tcl'*
 'tabclose' 'tcl'	string	(default "")