There is a JS library script tag on the site to try to correct the worst widows/orphans and some other typographic defects. It's after body load so as not to slow time to first paint and I don't think all browsers correctly readjust multi-column layout after its corrections/adjustment.

The caniuse statistics for CSS native support for widows/orphans correction is much better today than when I last worked on this CSS file: https://caniuse.com/css-widows-orphans