webix.Number.numToStr should consider the default decimal separator...

…based on the locale. Now, if decimalDelimiter is not specified, it’s output as undefined.

https://snippet.webix.com/tmo5knhq

Hello,

For locale-based number formatting, you can just define a built-in function:

 format: webix.i18n.numberFormat

https://snippet.webix.com/7smlz5ld

The webix.Number.numToStr function is designed for customizations and it awaits particular format parameters from you.