[eluser]Aken[/eluser]
There is no way to add attributes to a link like that without extending the Pagination class, so you were correct in doing that. The only extra thing you can add is a class name (or names) to each anchor.
I'm curious why you need a data-html attribute that just duplicates the normal href? It's already in that attribute, so you should be able to access it via Javascript no problem.
