Scott (@scottsweb)

Fillet adds a new IFrame button to the toolbar in the WordPress visual editor. By using a <a href="https://codex.wordpress.org/Shortcode" rel="nofollow ugc">shortcode</a>, it allows for safer, responsive and future proof embeds.
The chosen width and height for an IFrame embed is converted into a ratio which is used to scale your embeds across different devices.
<a href="http://scott.ee/" title="WordPress web design Hampshire" rel="nofollow ugc">a plugin by Scott Evans</a>

fillet

Safely embed responsive IFrames in the WordPress text editor.

YAHMAN

ZIPANG

Enclose the main points in a frame to make them stand out.
Other Credits
This plugin uses some icons from <a href="https://fontawesome.com" rel="nofollow ugc">Font Awesome</a>. 
License – (https://fontawesome.com/license/free) 
(Icons: CC BY 4.0 License , Fonts: SIL OFL 1.1 License , Code: MIT License)

Point Maker

Make a frame that can be easily used for the main points.

fillet vs Point Maker