Page: http://accessibility.psu.edu/tableshtml/complextablehtml/

Select the "color names in multiple languages..." header and table just below. The automation selection is the heading below that.

Selection:
> window.getSelection().toString()
"
Color Names in Multiple Languages (Romance vs Celtic)
Family	Romance Lang	Celtic
Color	Spanish	French	Irish	Welsh
Green	verde	vert	glas	gwyrdd
Blue	azul	bleu	gorm	glas
Black	negro	noir	dubh	du
"
> window.getSelection().getRangeAt(0)
Range {startContainer: div.example, startOffset: 1, endContainer: h2, endOffset: 0, collapsed: false, …}

Returned by automation:
The "About the Tags" heading as both the focus and anchor.
> anchorObject.name
"About the Tags"
> focusObject.name
"About the Tags"
> anchorObject.role
"heading"
> focusObject.role
"staticText"
> focusObject.parent.role
"heading"
> focusObject.parent === anchorObject
true


I can try to boil this down into a simple example later.