I had the same question and i use this new widget (https://appstore.home.mendix.com/link/app/111485/). This widget has the functionality you require.
With kind regards,
Bryan de Wit
Hi Jannes Houben
1. download 7zip extractor and go to widgets folder right click bootstrap datepicker.mpk file using 7zip extractor. click the open archive option.
2. you can able to see bootstrap-datepicker.js file
3. u will able to see the date format- like this (format: 'dd M yyyy',) in the bootstrap-datepicker.js file.
4. u can customize accordingly and it is done.
or try this customized widget