You are not missing anything. Here are some workarounds that come to mind.
One is to copy or move the forwarded message to a folder that signifies the recipient of the forward.
Another is to create an identity solely for use when bouncing a message. In it you would set a BCC address to yourself. Then, when you bounce a message, select the bounce identity in the lower part of the forward message window. The end result is that the copy of the message you receive back will contain a "Forwarded to:" header showing who you forwarded it to.
There is also the option of enabling SYSLOG.PM which logs all sent messages. It records the date, time, recipient, subject, sending identity, and two other fields whose purpose/content I don't know. I can not find documentation on the SYSLOG.PM file so don't know if there is a way to differentiate between bounced forwards and forwards with edits.
You are not missing anything. Here are some workarounds that come to mind.
One is to copy or move the forwarded message to a folder that signifies the recipient of the forward.
Another is to create an identity solely for use when bouncing a message. In it you would set a BCC address to yourself. Then, when you bounce a message, select the bounce identity in the lower part of the forward message window. The end result is that the copy of the message you receive back will contain a "Forwarded to:" header showing who you forwarded it to.
There is also the option of enabling SYSLOG.PM which logs all sent messages. It records the date, time, recipient, subject, sending identity, and two other fields whose purpose/content I don't know. I can not find documentation on the SYSLOG.PM file so don't know if there is a way to differentiate between bounced forwards and forwards with edits.