Historical clue formulations

• Secretly loop in on an email — 2026-04-07
• Email abbr. — 2025-12-06
• Secretly loop in, in a way — 2025-10-14
• "Moving to ___" (email phrase) — 2025-07-19
• Discreetly fill in, in a way — 2025-04-18
• Covert field? — 2025-02-08
• Surreptitiously let in on an email — 2025-01-21
• Concealed field, for short — 2023-08-13
• Email letters — 2023-03-03
• Include covertly in an email thread — 2023-01-24
• Secretly loop in by email — 2021-08-10
• Loop in on the DL — 2021-05-18
• Secretly include, maybe — 2020-10-08
• Loop in secretly, in a way — 2020-08-11
• Include surreptitiously, in a way — 2019-06-07
• Abbr. in an email field — 2019-01-08
• Emailing option — 2018-12-16
• Include covertly in an email — 2018-08-21
• Include without notifying others, in a way — 2018-02-25
• Send covertly, as an email — 2018-02-19
• Include discreetly, in a way — 2018-01-05
• Secretive email option — 2017-10-17
• Email letters — 2016-01-17
• Email add-on — 2015-09-16
• Include surreptitiously, in a way — 2015-04-26
• Abbr. at the top of an email — 2014-03-30
• Secret attachment, for short — 2013-08-03
• Letters in front of an e-mail address — 2012-08-08
• E-mail add-on — 2011-04-24
• Abbr. atop some e-mails — 2008-10-02
• Abbr. on top of some e-mails — 2007-08-05