Yeah, if $hyperkitty_url is expanded, e.g. in footer when message isn't archived, e.g. header has: X-Archive: no then $hyperkitty_url is still substituted, e.g.: https://lists.balug.org/mailman3/hyperkitty/list/balug-test@lists.balug.org/... Even though not archived and that URL gives 404 Not Found $ curl -s -I \
'https://lists.balug.org/mailman3/hyperkitty/list/balug-test@lists.balug.org/...' | head -n 1 | tr -d '\015'
HTTP/1.1 404 Not Found $ So, it essentially gives the URL of where it would be archived if it were archived, even when it's not archived at all.