if you're using english language, you can switch to Day/Month/Year by using 'English ' instead of 'English (US)', but there is yet no way to set a custom date format (ISO8601 for example) independent from language.
Might be covered by this feature request though, if I understand this Correctly
Thank you. setting UK English is a practical temporary solution. I continue to request this feature. Yes i think too can be covered by that feature request.
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Comment by FantasyDragon14
Comment by Eunoia