I’m working on removing the X-KumoRef header from our email headers. I noticed there’s a trace_headers option available in kumo.start_esmtp_listener, but I can’t seem to find an equivalent option for kumo.start_http_listener. This is particularly important for us since we’re sending all our emails through the HTTP API.
Set supplemental_header = false
cool, trying out now
I got this error:
Error: Initialization raised an error: call init callback: deserialize error: unknown field `supplemental_header`, expected one of `hostname`, `listen`, `use_tls`, `request_body_limit`, `tls_certificate`, `tls_private_key`, `trusted_hosts`, while processing {"listen":"0.0.0.0:8000","trusted_hosts":["127.0.0.1"],"supplemental_header":false}
Show your init.lua as per the bot READ ME FIRST message.
just a sec
That said, you shouldn’t need to remove the header because you inject over HTTP, the server adds it if not present and uses it for OOB bounces to get you useful information.
I added supplemental_header = false at line 112
ahhhh… I’m just experimenting with various ways to modify our header… ie, our email goes to spam
so I’m just randomly changing headers to experiment
(offtopic: we’re using sendgrid right now, and the deliverability is okay, might be with our IP or something)
(offtopic: we’re moving off from sendgrid to kumomta)
Ok, so the odds that the x-kumoref header is sending you to spam is slim to none.
oki… I guess I’ll just leave x-kumoref header then 
I’m off to warming up our new IPs!
thank you very much for you time, Mike
NP.