thunderbax

The plugin add a custom page in your admin dashboard where you can show html code to editors. 
You can edit the html text directly in a box place in option page with a WYSIWYG editor. 
All html, javascript, css are supported. 
You can also insert Youtube videos or images.
Related Links:
<ul>
<li><a href="http://www.thunderbax.com/?page_id=767" title="WP Admin Custom Page Plugin for WordPress" rel="nofollow ugc">Plugin Homepage</a></li>
<li><a href="http://www.thunderbax.com" title="Author Homepage" rel="nofollow ugc">Author Homepage</a></li>
</ul>

WP Admin Custom Page

The plugin add a custom page in your admin dashboard where you can show html code to editors.

Tammy Hart

Aaron Forgue

The Custom Class Selector plugin allows users to style their post content using 
custom classes made available by the active theme. Theme developers can make 
custom style classes available within the visual editor by adding a simple 
function to the functions.php file included with their theme.

Custom Class Selector

Allows users to style their post content using custom classes made available by the active theme.

WP Admin Custom Page vs Custom Class Selector