procmail's ^TO expansion does not include X-Original-To

[geofft]

Our FAQ says that you should look at the X-Original-To header. procmail has this nice ^TO_ header field:

If the regular expression contains ‘^TO_’ it will be substituted by ‘(^((Original-)?(Resent-)?(To|Cc|Bcc)|(X-Envelope|Apparently(-Resent)?)-To):(.*[^-a-zA-Z0-9_.])?)’, which should catch all destination specifications containing a specific address.

Meanwhile, we document:

You can access the tag on a message from your procmailrc file by parsing the X-Original-To header or as the $1 variable.

Note that the regex matches Original-To but not X-Original-To.

A request to match X-Original-To too should be filed upstream with procmail, unless X-Original-To is a thing we do and not that procmail/postfix does in which case we should switch to Original-To, or unless it's a thing that postfix does in which case we should file a bug with them telling them to switch to Original-To.