If you are competent in HTML coding, you can get down to the nitty gritty and edit the raw HTML code of your content. (Most of this text was written using this functionality, though all examples used the WYSIWYG editor.)

1. Click the button.
2. Edit the HTML directly. Line breaks, styles, tables, lists, etc. can be all changed manually.
3. When you're done, click the button again. Changes you made should be reflected in the WYSIWYG editor. The editor closes any unclosed tags, and makes a "best guess" where the closing tags should go, so changes may not fully reflect the author's intent.