On my calendar page (I use Full Calendar) the All event categories dropdown box is always opened and without any styling.
Until today it works fine and was closed before clicking on it to see the categories (as it must be).
But today it changed. It seems that the page doesn't find the styling of this drop domn menu.
What can it be?
I upgraded to WP 3.6 but I think it was later in the day...
Thank you for your help.