don`t work uploader addFile function

https://snippet.webix.com/2xvxl6bh
say me pls haw we can fix this?
Function send me error on cant read property ‘webkitRelativePath’ in file object
if (file.webkitRelativePath)
file_struct.name = file.webkitRelativePath;
Version 5.4.3

Hello,

Yes, it’s a known bug. We investigate the problem and will fix it in the near future.
If you need the fix ASAP and have a support subscription, please contact support@webix.com.