Add support for the Sender header

[binki]

I have emails for which the Sender header has significance and is different from the From address. This happens when emails are forwarded in a special way by Outlook. Outlook will display “Sent by «Sender header» on behalf of «From header»”. Please see [https://www.reddit.com/r/Thunderbird/comments/10eqlmy](this Reddit thread) for another example.

I thought that the “Sender” column would be from the Sender header because of its name. However, it is actually from the From header.

Can you add a new set of columns from the Sender header?

Thanks.