Codetch is a cool Firefox plugin that provides a fully featured WYSIWYG web editor right there inside the browser. Tabbed windows, previews, Javascript debugger, it’s all there. It’s fast, open source and a rather cool bit of tech.
If you can run Firefox, Thunderbird, or Mozilla on your computer and have one of them installed, then yes, you too can use Codetch. The program currently installs as an extension for either of the before mentioned applications. So if you are using one of them, you should also be able to install Codetch. Codetch is free of course, and is open source.