Update runtime files
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index f884448..f210d31 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt* For Vim version 8.2. Last change: 2021 Sep 21
+*options.txt* For Vim version 8.2. Last change: 2021 Oct 20
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -717,7 +717,8 @@
"double": Use twice the width of ASCII characters.
*E834* *E835*
The value "double" cannot be used if 'listchars' or 'fillchars'
- contains a character that would be double width.
+ contains a character that would be double width. These errors may
+ also be given when calling setcellwidths().
The values are overruled for characters specified with
|setcellwidths()|.