Historical clue formulations

• Before: Abbr. — 2020-11-29
• <<< button: Abbr. — 2020-08-05
• "Go back" button abbr. on some remotes — 2018-08-11
• Before: Abbr. — 2017-05-21
• Earlier: Abbr. — 2017-04-19
• Prior: Abbr. — 2016-02-05
• Before: Abbr. — 2012-12-22
• Before: Abbr. — 2005-02-21
• Beforehand: Abbr. — 2004-10-31
• Before: Abbr. — 1999-10-20