diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index fd0b453ffe..79ddeb8e06 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -2540,14 +2540,14 @@ 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: >c
+	names, it should therefore not be used for a filetype.  Example: >c
 		/* 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 "")
@@ -3700,7 +3700,7 @@ 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 "")
@@ -6404,7 +6404,7 @@ 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 "")
diff --git a/runtime/lua/vim/_meta/options.lua b/runtime/lua/vim/_meta/options.lua
index 04e573c3ed..c48fbab431 100644
--- a/runtime/lua/vim/_meta/options.lua
+++ b/runtime/lua/vim/_meta/options.lua
@@ -2218,7 +2218,7 @@ vim.go.fic = vim.go.fileignorecase
 --- ```
 --- `FileType` `filetypes`
 --- When a dot appears in the value then this separates two filetype
---- names.  Example: >c
+--- names, it should therefore not be used for a filetype.  Example: >c
 --- 	/* vim: set filetype=c.doxygen : */
 --- ```
 --- This will use the "c" filetype first, then the "doxygen" filetype.
@@ -2226,7 +2226,7 @@ vim.go.fic = vim.go.fileignorecase
 --- 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.
 ---
 --- @type string
 vim.o.filetype = ""
@@ -3604,7 +3604,7 @@ vim.go.jop = vim.go.jumpoptions
 --- 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.
 ---
 --- @type string
 vim.o.keymap = ""
@@ -6874,7 +6874,7 @@ vim.bo.smc = vim.bo.synmaxcol
 --- 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.
 ---
 --- @type string
 vim.o.syntax = ""
diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index 0da954d052..61dc1a8daa 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -2832,14 +2832,14 @@ return {
         	/* vim: set filetype=idl : */
         <	|FileType| |filetypes|
         When a dot appears in the value then this separates two filetype
-        names.  Example: >c
+        names, it should therefore not be used for a filetype.  Example: >c
         	/* 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.
       ]=],
       full_name = 'filetype',
       noglob = true,
@@ -4571,7 +4571,7 @@ return {
         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.
       ]=],
       full_name = 'keymap',
       normal_fname_chars = true,
@@ -8542,7 +8542,7 @@ return {
         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.
       ]=],
       full_name = 'syntax',
       noglob = true,