Cannot read property 'category' of undefined

-- HikaShop version -- : 2.4.0
-- Joomla version -- : 3.4.0
-- Error-message(debug-mod must be tuned on) -- : Uncaught TypeError: window.oNamebox is not a function
Uncaught TypeError: Cannot read property 'category' of undefined

Hello everyone,

Today i find issue, when tried to add additional field. How to fix it?
I didn't change js files in "media/com_hikashop". On previous version of hika it worked well, but now it doesn't work

I didn't do anything but error was fixed without my help.