Can't load image to variants

-- HikaShop version -- : 2.5.0
-- Joomla version -- : 3.4.3
-- PHP version -- : 5.4.44
-- Browser(s) name and version -- : any browser
-- Error-message(debug-mod must be tuned on) -- : Choosing the variant:
Uncaught SyntaxError: Unexpected token }
Oby.updateElem @ hikashop.js?v=250:235
xhr.onreadystatechange @ hikashop.js?v=250:175

Trying to upload the variant image:
Uncaught TypeError: Cannot read property 'uploadFile' of undefined
onclick @ index.php?option=com_hikashop&ctrl=product:1

Hello!
I can't add images for product variants. Image module looks like this (arrow points at "Browse" button): joxi.ru/gmv6V7yIOdkDma
Clicking on "Upload" button causes nothing but scrolling up to the top of the page.
Please, help me!

Nicolas, please look at the first post: we have Joomla 3.4.3, not 3.4.4. What should I do? Update to 3.4.4?

Edit:
There's one more error. Clicking on "Variants" tab cause this: joxi.ru/1A5QJW7IdlJYAE
Error:
Uncaught SyntaxError: Unexpected token }
Oby.updateElem @ hikashop.js?v=250:235
xhr.onreadystatechange @ hikashop.js?v=250:175
VM4826:263

Thanks, we'll try