Sonarr/src/UI/Activity/History/Details/HistoryDetailsAge.js

var Handlebars = require('handlebars');

Handlebars.registerHelper('historyAge', function() {

    var unit = 'days';
    var age = this.age;

    if (age < 2) {
        unit = 'hours';
        age = parseFloat(this.ageHours).toFixed(1);
    }

    return new Handlebars.SafeString('<dt>Age (when grabbed):</dt><dd>{0} {1}</dd>'.format(age, unit));
});