Note that I work on osTicketAwesome version so something may differ, but the translation is missing in vanilla too.
What I've found out is that at the time of injecting timepicker to the datepicker, in the context there is missing the translation in datapicker defaults.
- So I've forced it to load translation from the global context in
_injectTimePicker
function in /js/jquery-ui-timepicker-addon.js
$.extend(o, jQuery.datepicker.regional[Object.keys(jQuery.datepicker.regional)[Object.keys(jQuery.datepicker.regional).length - 1]]);
Then I had to additionally translate pop up texts (now, done) at the end of injection.
$('.ui-datepicker-close').text(o.closeText);
$('.ui-datepicker-current').text(o.currentText);
Also I had to extend translations to the i18n files like /include/i18n/pt_PT/js/jquery.ui.datepicker.js
timeText: 'Czas',
hourText: 'Godzina',
minuteText: 'Minuta',