Hi,
I decided to try adding Chosen to the drop down date field. But GF adds the same ID to each select menu when using it. The only select menu that gets the Chosen style properly is the first instance (taking values from the last instance).
So the day, month and year select menus all have the same ids. The normal functionality works, but the HTML isn't valid. And Chosen doesn't work either.
I managed to make it work using some hacky preg_replace;
//Day
$content = preg_replace("/(<div class='gfield_date_dropdown_day[^>]+\>)(<select name='input_\\d{1,2}\[\]' )(id='input_\\d{1,2}_\\d{1,2}_\\d{1,2})/s", "\$1$2$3_1", $content);
//Month
$content = preg_replace("/(<div class='gfield_date_dropdown_month[^>]+\>)(<select name='input_\\d{1,2}\[\]' )(id='input_\\d{1,2}_\\d{1,2}_\\d{1,2})/s", "\$1$2$3_2", $content);
//Year
$content = preg_replace("/(<div class='gfield_date_dropdown_year^>]+\>)(<select name='input_\\d{1,2}\[\]' )(id='input_\\d{1,2}_\\d{1,2}_\\d{1,2})/s", "\$1$2$3_3", $content);