A fact from The Mass Extermination of Jews in German Occupied Poland appeared on Wikipedia's Main Page in the Did you know column on 6 September 2018 (check views). The text of the entry was as follows:
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See the Propaganda article for details how British WWI propaganda was debunked in around 1926 by press and how it made US and UK public suspicious of such future claims, including tragically true ones, like these.