Now that Puffin has finally quit altogether as of July, this is a loss. They were one of the only iOS browsers that could actually scroll Disqus comments, commonly found on news sites, correctly. Safari, Chrome, Firefox, Brave? Nope.
(Though I’m still not clear as to whose fault the scrolling problem is, iOS or elsewhere. Could be the site designer’s haven’t implemented the Disqus popup frame correctly.)
No alternative since Apple changed their policy. All browsers are required to use WebKit. That’s the reason why puffin could no longer push updates to their app.