How to get serializeNodeToJsonMl?
import serializeNodeToJsonMl from 'fontoxml-dom-utils/src/serializeNodeToJsonMl.js'
Creates a JsonML representation for the given node.
As Document nodes are not supported in JsonML, pass Document.documentElement if you need the JsonML representation of a complete document, otherwise Document will be represented as an element with an unexpected nodeName. This will not round-trip.
Root node of the structure to convert.