Is it possible to suppress the "signed-by" and "mailed-by" headers that sendgrid adds to white-labelled mail? (Paid account.)
Is it possible to selectively suppress them on some mail and not other mail?
Is it possible to suppress the "signed-by" and "mailed-by" headers that sendgrid adds to white-labelled mail? (Paid account.)
Is it possible to selectively suppress them on some mail and not other mail?
No. It is not possible to selectively suppress the mailed-by and signed-by headers unless and until SendGrid provides such functionality which I don't think they will. There is currently no way to even suppress those headers for all your emails, as far as I can determine. It appears that SendGrid ALWAYS includes those headers and does not provide a way to turn them off.
Are you referring to the Headers, or the "on behalf of" type headers that show up in some mail reader views?
The "on behalf of" type headers are added by the Mail Reader, but if you Whitelabel in SendGrid, that will not be triggered.
If you're talking about the deeper headers, what's the use-case? Those aren't displayed to the end user that I've ever seen.