Thanks to Manassas for the logo (see below)

LOGO
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The logo is derived from the blason of Nancy (France) as created by Manassas:
  "Manassas Image created for the Blazon Project of the French Wikipedia.
     [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]"
So the logo is also available using the same license.