I currently live in the UK & Firefox defaults me the UKs common sociatal date format D-M-Y, due to having the language set to British English (GB) but the UK also uses International Date Standard ISO 8601 YYYY-M D & I have used this exclusively for the past 20+ years. My computers OS is set to the international standard.

Is there a way to set Firefox to use this date standard? I'd be happy to set the date region to Japan & have it in Japanese, they use International Standard & I lived there for many years, so that would be an acceptable option.