Does your browser have sidebars? You can add sidebars if you want to reduce the width of the document, I suppose. (There is bookmark sidebar, history sidebar, and web developer sidebar; what I think is missing is the table of contents sidebar, which would list the <h1>, <h2>, etc in the current document. Another thing that might be wanted is split-screen mode, I think.) I personally do want a full-screen line of text, although I suppose some people do not want.