Object.create(null) т.е. без стандартного прототипа.Object.hasOwnProperty.call(lo.cache, 'property-name')
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var sizeEmpty = form.find('.empty_field').size();var sizeEmpty = form.find('.empty_field').length;The .size() method is deprecated as of jQuery 1.8. Use the .length property instead.
removed: 3.0
