Guahan Web

<p>This plugin gives you the flexibility to add Ajax handling for your comments to keep the page from having to refresh every post. The administration panel will allow you to customize your processing, success and error messages.</p>
<p>Additionally, this plugin gives you the option of setting up the WYSIWYG editor for comment submission as well. The admin panel will give you the option to show/hide various button groups for the editor and only allows basic editing capabilities. If logged in as administrator, you will still receive the full WYSIWYG editor for your commenting.</p>


GuahanWeb AJAX & WYSIWYG Comments

Adds customization for Ajax commenting and allows for enabling of custom WYSIWYG editor.

LuckyWP

<p>The plugin replaces plain-text editor for category, tag and custom taxonomy term description with the built-in WordPress WYSIWYG editor (TinyMCE).  This is allow you to insert images, use shortcodes, embed videos, audio and other content into term description.</p>
<h4>Features</h4>
<ul>
<li>Edit category and tag description with built-in WordPress WYSIWYG editor (TinyMCE).</li>
<li>Work in add and edit term forms.</li>
<li>Support WooCommerce category and tag description.</li>
<li>Support custom taxonomy term description.</li>
</ul>


LuckyWP Term Description Rich Text

Thanks to the author for the work. I already use on two sites

Very useful plugin

Replaces plain-text editor for category, tag and custom taxonomy term description with the built-in WordPress WYSIWYG editor (TinyMCE).

GuahanWeb AJAX & WYSIWYG Comments vs LuckyWP Term Description Rich Text