Dave Ryan

Create chat threads using WordPress Blocks inside app and mobile wrappers.
Chatterbox can be used for: 
* Demos of chat bots 
* Publishing chat records in news stories 
* A fun way to add striking visual display to conversations
At launch, Chatterbox allows display of chats with messages and timestamps in inbound and outbound styles.
Chat threads can be displayed without a background, in an app container, in mobile phones and other computer screens.
Learn more about what’s <a href="https://github.com/0aveRyan/chatterbox#roadmap" rel="nofollow ugc">on the roadmap</a>.

Chatterbox

Create chat threads using WordPress Blocks inside app and mobile wrappers.

Dreb Bitanghol

This field will provide you more options and flexibility on how you would like to present an instruction or message to your client’s (or site in general) admin interface.
Features:
<ul>
<li>Support PHP.</li>
<li>Option to hide label when field is displayed.</li>
</ul>
Compatible with Advanced Custom Fields:
<ul>
<li>4 (tested up to 4.4.6)</li>
<li>5 (PRO, tested up to 5.3.7)</li>
</ul>
PS: You need <a href="https://wordpress.org/plugins/advanced-custom-fields/" rel="ugc">Advanced Custom Fields</a> installed to use this.
PPS: Even more awesome if you have <a href="http://www.advancedcustomfields.com/pro/" rel="nofollow ugc">Advanced Custom Fields PRO</a> installed.
Important note: Use this with utmost care.

ACF Enhanced Message Field

Exactly what I needed

Exactly what I needed. You could improve the plugin by making the textarea field look more like an IDE, with system fonts, syntax highlights and so on.

Perfect

Awesome!!

Adds an enhanced version of the default Message field to accept PHP and certainly no wpauto().

Chatterbox vs ACF Enhanced Message Field