Working with JavaScript and named flows
The article flow does NOT fit in the region chain.
Hint: resize the browser window and check out the JavaScript source code of this page.
Named flows created from CSS have a corresponding DOM object. This object has a reference to its content elements and it can tell they fit completely into the region chain.
Code sample
var flow = document.getNamedFlows()['article']
flow.contentNodes // NodeList
flow.overset // boolean
'flow' is an instance of NamedFlow
A named flow is represented by a NamedFlow object. The document.getNamedFlows() method returns a NamedFlowCollection object – individual named flows can be retrieved either by index or by name from this collection.
The contentNodes property references a NodeList of elements which are collected into the named flow.
The NamedFlow object has a boolean property called overset. If the flow's content fits completely in the region chain then the value of overset is false, otherwise it is true.