Rated 5 out of 5 stars

I'm trying to find what appears to be the Holy Grail of forwarding for Thunderbird, the ability to automatically take any message landing in a specific Inbox from a specific verified sender and then redirect it as BCC to a list of recipients.

All the solutions I have found so far fail.

I thought Use Bcc Instead would be the solution to the defect in the built-in TB functionality, namely the 'Forward To' option within TB message filters, however, despite telling Use Bcc Anyway to always convert To: and Cc: to Bcc: in all outgoing messages, the mail forwarded by the message filter is still sent using a To: header.

Shame, I thought it would work.

[ review amended from 1 star to 5 stars after complaint by developer]

You complain about an addon NOT doing what you want even though it never claimed to do so. You yourself say it was your Holy Grail and that nothing else does what you want. Then you give a 1-star review to an addon that never was designed or intended to be what you want: a filter action. One can understand your disappointment. But not your lame and unwarranted 1-star rating.