Tu mac guarda un log con todo lo que descargas

Good Morning, Your Mac Keeps A Log Of All Your Downloads

Para ver el log escribe en el Terminal:

sqlite3 ~/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV* 'select LSQuarantineDataURLString from LSQuarantineEvent'

Y para borrar el log:

sqlite3 ~/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV* 'delete from LSQuarantineEvent'

Si quieres automatizar el borrado con Keyboard Maestro u otro programa similar, usa este Applescript:

do shell script "sqlite3 ~/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV* 'delete from LSQuarantineEvent'"