Comment 36 for bug 237341

Ok, I looked into the issue of how to determine the first day of the week. There's a localization file here, used for the datepicker[1] and there's also a pref in Lightning[2]. I'm pretty sure most OSes also specify this somewhere, but we don't detect that. I'm CCing one of the Lightning devs so that we can discuss the correct solution here. It might be useful to add support to Gecko to pull this in from the OS; that could be useful for HTML5 forms as well.

[1] http://mxr.mozilla.org/comm-central/source/mozilla/toolkit/locales/en-US/chrome/global/datetimepicker.dtd
[2] http://mxr.mozilla.org/comm-central/source/calendar/locales/en-US/lightning-l10n.js#9