Debiprasad Sahoo

This is a very simple sidebar widget which places javascript code in the widget. You need to provide only the script (while editing the widget), this widget will place this code inside javascript blocks.
You can also able to add JavaScript codes in text widget in sidebar. So you don’t need this plugin.

JavaScript Block Widget

Widget plugin to run any JavaScript in the sidebar

Frank Goossens

Optimizing Matters

EricJohnsonGuru

Eliminate Render-blocking Javascript in above-the-fold content with Async Javascript.
Render-blocking Javascript prevents above-the-fold content on your page from being rendered until the javascript has finished loading. This can impact on your page speed and ultimately your ranking within search engines. It can also impact your user’s experience.
Async JavaScript gives you full control of which scripts to add an ‘async’ or ‘defer’ attribute to or to exclude to help increase the performance of your WordPress website.

Async JavaScript

Plugin works as expected, settings are nice and minimal (using core styles) and there aren't any banners, notices or other marketing bloating things up.

Works great!

Async Javascript lets you add 'async' or 'defer' attribute to scripts to exclude to help increase the performance of your WordPres …

JavaScript Block Widget vs Async JavaScript