[csuwldcat]

I believe you are describing the native datepicker, I am seeing the same weirdness. Be advised, the calendar polyfilled calendar is only active when a native implementation is not detected, or you force it to be used. This may be a bug in Chrome itself.

[nogridbag]

Yes you're correct. It's neat that it uses the native datepicker if available, but one area of concern is they use different date input formats. Native forces mm/dd/yyyy while the polyfill suggests yyyy-mm-dd (though it accepts the former format as well).