Looking at Apple's Mail: Show detailed message headers, it sounds like I shouldn't be seeing
Resent-from headers, because I have the View->Show message headers preference set to "Default."
The support page sounds like I should need to use Custom to ever see Resent-from.
How can I turn off the
I also tried setting the preference to Custom... without adding any headers at all, and nothing changed.
My Mac is running OS X 10.10.5, Yosemite.