Historical clue formulations

• "Can it!" — 2021-06-23
• "Button your lip!" — 2017-03-13
• "Zip it!" — 2013-07-07
• "Shhh!," not so politely — 2009-10-22
• "Zip it!" — 2004-04-23
• "Stop talking!" — 2000-01-03