We already have a much easier way to do this through a bookmarklet, which doesn't involve trusting an extension: https://news.ycombinator.com/bookmarklet.html

It's one line of JS that you can inspect right here:

    javascript:window.location=%22http://news.ycombinator.com/submitlink?u=%22+encodeURIComponent(document.location)+%22&t=%22+encodeURIComponent(document.title)