matteotrap

WordPress Excerpts should be short, you know.
But when a user writes a lot, you might want to limit the number of characters for the excerpt panel: that’s where the Excerpt Character Limiter plugin comes handy!
It will basically add a character countdown to the panel titlebar, and it will truncate the text when available characters drop to zero. 
Simple but effective!

Excerpt character limiter

It will basically add a character countdown to the panel titlebar, and it will truncate the text when available characters drop to zero.

Simon Wheatley

This is a simple plugin that enables rich text editing on the excerpt field.
If you have any plugins installed which alter TinyMCE, e.g. to add additional 
buttons, they will also be applied to the excerpt editor.
Any issues: <a href="http://www.simonwheatley.co.uk/contact-me/" rel="nofollow ugc">contact me</a>.
<h3>Known issues / bugs</h3>
Please <a href="http://www.simonwheatley.co.uk/contact-me/" rel="nofollow ugc">report any issues</a> that you find.
<ul>
<li>In WordPress versions prior to WordPress 2.5, when you click the “advanced toolbar” button, the advanced toolbar shows up on the 
Content, rather than the excerpt. Reported by <a href="http://hypenotic.com/" rel="nofollow ugc">Jorge Villalobos</a></li>
<li>You can’t send images to the excerpt editor from the edit page file browser; 
you have to send them to the main editor, then copy and paste.</li>
<li>To show the excerpt you have to use a template which uses 
<a href="https://codex.wordpress.org/Template_Tags/the_excerpt" rel="nofollow ugc">the_excerpt</a>, rather 
than <a href="https://codex.wordpress.org/Template_Tags/the_content" rel="nofollow ugc">the_content</a>.</li>
</ul>
<h3>Requests</h3>
I’m simply noting requests here, I’ve not necessarily looked into how possible any of these are or how much effort they might require.
<ul>
<li>It would be great if you could switch between TinyMCE and Quicktags as the content does. Requested by <a href="http://hypenotic.com/" rel="nofollow ugc">Jorge Villalobos</a></li>
</ul>

TinyMCE Excerpt

Enables rich text editing on the excerpt field.

Excerpt character limiter vs TinyMCE Excerpt