ぽぽろん＠ぽぽづれ。

これはビジュアルエディタでHTMLタグを直接表記するプラグインです。
主にテキストモードに切り替えるのが面倒なときに使います。
<h3>Arbitrary section</h3>

Pz-DirectHTML

ビジュアルエディタだってHTMLしたい。

Pavel

A lightweight plugin for creating and managing custom text shortcodes.
With this plugin, you can create an unlimited number of custom text shortcodes via the WordPress admin panel. Each shortcode can contain any text or HTML content, such as ads, banners, counters, or reusable blocks of content.
All created shortcodes are listed in an admin table for easy access and management. 
Shortcodes are stored in a separate custom database table. 
Each shortcode is automatically assigned a unique name in the format <code>[mtsc-name-id]</code>, where <code>mtsc-</code> is the default prefix to avoid conflicts with other shortcodes.

My Text Shortcodes

A lightweight plugin for creating and managing custom text shortcodes.

Pz-DirectHTML vs My Text Shortcodes