NoSquint is a Firefox add-on that allows you to adjust the text-only and full-page zoom levels as well as color settings both globally (for all sites) and per site.
Version 2.1.8 doesn't work in Firefox 20. Went back to version 2.1.6 and it now shows zoom level in lower right tab again and remembers zoom level. Version 2.1.8 has a major bug.
Version 2.1.8 doesn't work in Firefox 20. Went back to version 2.1.6 and it now shows zoom level in lower right tab again and remembers zoom level. Version 2.1.8 has a major bug.