WordPress automatically inserts p and br tags, but disables them in shortcodes.

ReynoldsTimJ

Line Break Shortcode

Use this to force line breaks into your posts and pages. It is simple. [br] will add a line break. It won't be filtered out by TinyMCE.

YAHMAN

ZIPANG

When you enter the HTML code directly, the layout changes depending on the p and br tags that WordPress automatically inserts.
<pre><code>remove_filter( 'the_content', 'wpautop' );
</code></pre>
It can be solved by adding the above code. 
However, this will disable all auto-inserted p and br tags. 
It is not user-friendly.
This plugin can be partially disabled.
Just enter the part you want to disable in the shortcode.
<pre><code>[jo]your HTML code[/jo]
</code></pre>
The author of this plugin loves text editors.

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