lzw.

A plug-in can enable all classic functions, and also contains some practical functions
<ol>
<li>Register hierarchical posts to build documents</li>
<li>Enable Link Manager</li>
<li>Enable Classic Editor</li>
<li>Enable Classic Widgets</li>
<li>Gravatar Mirror Server</li>
<li>In archive and home page display the post excerpt</li>
<li>Password protected posts only the content after <code><--more--></code> require password</li>
<li>Use vuejs and <code><div class="html-demo"></div></code> to preview html code</li>
<li>Img Src Prefix, like a CDN</li>
<li>Enable Login Limit</li>
<li>Enable SMTP Email</li>
<li>Highlight Style</li>
</ol>

ClassicPlus To Enable Classic Functions

A plug-in can enable all classic functions, and also contains some practical functions

mch0lic

Recently upgraded to WordPress 3.8+ and not yet ready for the visual change? WP Admin Classic plugin simply disables new admin theme and reenables the prior 3.8 looks to your admin panel. Please, note that there is still some unsolved issues (see “Issue list), so if you have ideas how to solve it just shout!
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Issue list:
<ol>
<li>
RTL Languages are not yet supported!!!
</li>
<li>
Post edit form turns blue (as a result for fixing http://1?ver=3.8 issue)
</li>
<li>
Admin bar is not displayed properly on front-end with standard Twenty Thirteen, Twenty Fourteen (updated themes).
</li>
</ol>
Notes:
<ol>
<li>Dashboard widgets are now 100% wide. CSS fix by Robert Heller (Single column only!).</li>
</ol>
Please, report any other CSS/JS issues and suggestions how to fix them <a href="https://wordpress.org/support/plugin/wp-admin-classic" rel="ugc">here</a> or <a href="http://mindomobile.com/contact-us/" rel="nofollow ugc">here</a>. Your help much appreatiated.
ENJOY!

wp-admin classic

Classic WordPress Admin theme (prior 3.8 style).

ClassicPlus To Enable Classic Functions vs wp-admin classic