We would like to thank:
Dave Brasgalla from Iconfactory for the World Clock Deluxe application icon and for the Clocks, Cities & Time Zones, and Time Converter toolbar icons used on macOS 10.15 or earlier;
Patrick Van der Perre for his comments and suggestions and the Dutch localization of World Clock Deluxe;
Steffen Thorsen for creating and maintaining the timeanddate.com website.