What is the problem here?

well,

The fact is sunday is the last day of week for a vast majority of countries and defined ISO 8601. Except for US and other metric system haters.

As sunday the last and so monday the first, it should be represented like this in a week calendar. I often make mistake selecting wrong day in datepicker due to this.

Change this setting in config would be very appreciated.

I see. Thanks for the explanation.

Except for US and other metric system haters.

This sentence is a bit too offence imho.

Anyway I agree with bufferUnderrun. A locale setting for dates and other formats would be a nice feature.

Thinking more about that there should be a server setting with the default locale. An user should be able to override it. In addition to that per default the locale should be picked up by the browser settings.

I agree that OneDev should detect locale from browser automatically. A server locale setting might not be very useful as different user may have different locale.

The file date-picker.js contain the logic of calling flatpickr to display the date picker. We should be able to detect browser locale here and call with appropriate options.

I have just started implementing this: pull request onedev-server#25