Ask HN: Browser Extension for DRY headlines and posts?

Does anyone know of an extension or have an idea on how to best write one to prevent the insanely repititous viewing of headlines, posts, and links across the top media(social and news) sites? I effectively want an add blocker for everything I have seen before. Building and maintaining what is effectively an adblocker targeting the CSS HTML and JS from scratch on my own is not possible.