See the question and my original answer on StackOverflow

In pure XPATH over XML, you would use an XPATH expression like this: //preceding-sibling::br or //following-sibling::br (see here for help on XPATH Axes)

But, the XPATH over HTML implementation that you'll find in Html Agility Pack does not support pure text node or (Attribute node) in XPATH selection expressions (//br/text() or //br/@blah do not work for example). Note it works in filters, so, these //br[text()='blah'] or //br[@att='blah'] work.

So, back to the question, you need to combine XPATH and code, something like this:

HtmlDocument doc = new HtmlDocument();
doc.Load(myHtmlFile);

foreach (HtmlNode p in doc.DocumentNode.SelectNodes("//br"))
{
    Console.WriteLine(p.PreviousSibling.InnerText.Trim());
}

That will output

Jack Janson
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