well, we had a variable UnrecognizedBounceNotify here in https://github.com/wikimedia/mediawiki-extensions-BounceHandler/blob/master/extension.json#L41, which is unset in production cluster, raising this error message.

This message was removed in https://gerrit.wikimedia.org/r/#/c/253140/, thank you @Reedy

Do we need to email someone regarding temporary bounce, so that we can analyse the headers ?

This might be a duplicate of T99458 though.

In T118667#1806465, @01tonythomas wrote:

well, we had a variable UnrecognizedBounceNotify here in https://github.com/wikimedia/mediawiki-extensions-BounceHandler/blob/master/extension.json#L41, which is unset in production cluster, raising this error message.

This message was removed in https://gerrit.wikimedia.org/r/#/c/253140/, thank you @Reedy

Do we need to email someone regarding temporary bounce, so that we can analyse the headers ?

Well, it was unset, and the variable usage was also wrong (also fixed, then reworked!)

The debug message was pointless, as it wasn't accurate, and was just mostly noise anyway.

The question is whether we should be sending notifications to admins at all, in the case of temporary bounces. I guess for WMF wikis, at least, this isn't going to be set in most cases, probably only some of the small or private wikis are likely to want to use it