btcpayserver/BTCPayServer/wwwroot/main/site.js

$(function () {
    $(".localizeDate").each(function (index) {
        var serverDate = $(this).text();
        var localDate = new Date(serverDate);

        var dateString = localDate.toLocaleDateString() + " " + localDate.toLocaleTimeString();
        $(this).text(dateString);
    });
});