THATplugin

Quickly and easily iconize posts, pages, menu items, widget titles, taxonomies, and pretty much everything, using icon picker with plenty of customization options. No shortcodes. No coding skills required. Developer friendly.
Iconize is here to make your life easier, by providing simple and easy to use interface for inserting icons.
Features:
<ul>
<li>8 Optional Icon Fonts included – Dashicons, Font Awesome 4.7, Font Awesome 5 Free (Solid, Regular, Brands), Bootstrap Icons, Foundation 3 Icons and Iconoir</li>
<li>Upload custom fonts</li>
<li>The only actual WYSIWYG icons classic editor plugin (works inside Gutenberg classic editor block)</li>
<li>Menu icons (Customizer support)</li>
<li>Widget title icons (Customizer support)</li>
<li>Post Categories, Post Tags, Custom Taxonomy icons</li>
<li>Effects, color, size, alignment, custom CSS classes options</li>
<li>26 CSS transform options</li>
<li>13 CSS animation options</li>
<li>56 CSS hover effects</li>
<li>Optionally use included fonts inside popular free page builders (Elementor, Beaver Builder, Page Builder by SiteOrigin)</li>
<li>CMB2 Custom field</li>
</ul>
Getting started:
Here’s a link to our <a href="https://thatplugin.com/docs/iconize/" title="Iconize Documentation" rel="nofollow ugc">Documentation</a>, we doubt that you’ll need anything else but feel free to ask if you have any question.

Iconize

Quickly and easily insert icons to posts, pages, menu items, widget titles, taxonomies using icon picker with plenty of customization options

joe_bopper

Adds search box as a choice of item in navigation menus admin area.
Features include:
<ul>
<li>now compatible with the WordPress appearance customizer,</li>
<li>search box available as a choice in the admin area for navigation menus,</li>
<li>as many boxes can be added to a nav menu as one likes,</li>
<li>search boxes can be added as children of other menu items (useful for, e.g., mega-menus),</li>
<li>capacity to change button text, placeholder and css classes from the admin area to each search box,</li>
<li>hooks to modify output (see FAQ and/or code comments),</li>
<li>very lightweight,</li>
<li>in keeping styles, html, behaviour, etc., with wordpress defaults,</li>
<li>works straight out of the box, no configuration needed.</li>
</ul>
<h4>Those wanting to translate this plugin, please do.</h4>
I believe the plugin is in a translatable state and I’ll do everything I can to help in translation. It should be relatively quick as there isn’t much text to the plugin.

Bop Search Box Item Type For Nav Menus

I like the way it behaves like any menu item so you can position and decorate it how you want. Thanks to Joe for putting me right on how to get at the placeholder text.

Nice Plugin

Adds search box as a choice of item in navigation menus admin area.

Iconize vs Bop Search Box Item Type For Nav Menus