Brackets is an open source code editor for web designers and front-end
developers.

Google Chrome or Chromium is currently required to use the live preview
function, Firefox support is planned for the future.

As of version 1.0, the Extract bundle is now included, more details here:

http://blog.brackets.io/2014/11/04/brackets-1-0-and-extract-for-brackets-preview-now-available/