type.inbound
and any(body.links,
// link type digit (4 = click, 5 = unsubscribe), then digit fields split by fixed-length letter filler
regex.contains(.href_url.url,
'\b[45][A-Za-z]{5}\d+[A-Za-z]{4}\d+[a-z]{10}\d+[A-Z]{15}\d+[A-Z/]{1,4}\d+[A-Za-z]\d+\b'
)
)
Playground
Test against your own EMLs or sample data.