Russ Allbery wrote, | I don't know about procmail itself ... | But surely such a widely-used filtering mechanism has something in place | to handle folded headers.
Procmail's internal egrep-substitute treats an indented line in the head (but not in the body) as extensions of the line before it; the newline is converted internally to a space. So a folded List-ID: header line is not an issue.
