Add test for gettabvar() and settabvar().
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 8c8006c..498df7f 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1450,6 +1450,8 @@
as HTML. This works to copy rendered HTML from
Firefox, paste it as raw HTML in Vim, select the HTML
in Vim and paste it in a rich edit box in Firefox.
+ You probably want to add this only temporarily,
+ possibly use BufEnter autocommands.
Only supported for GTK version 2 and later.
Only available with the |+multi_byte| feature.