No, there is no documentation for Handlebars integration. There isn't much to document though - everything you need to do is this:
template: Handlebars.compile("some handlebars template"
The template option can be set to a function which returns an HTML string. In this case Kendo UI will use the function as it is and won't try to compile it as a Kendo UI template.
We haven't conducted thorough tests to find out how much of Handlebars is supported. We are not aware of any issues though.
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