Justin Tadlock

JavaScript Logic is a plugin that allows you to add JavaScript however you want. There’s no need to add a script on all of your blog’s pages when you only need it on a few.
By using WordPress conditional tags or through a meta box on the Write Post/Page screen, you control what files are added to your site and when.

JavaScript Logic

Allows you to load JavaScript in a much more controlled way using WordPress conditional tags.

WordPress.org

Andrew Ozz

Marius L. J.

With the update to WordPress 5.5, a migration tool known as <code>jquery-migrate</code> was no longer enabled by default. This may lead to lacking functionality or unexpected behavior in some themes or plugins that run older code.
This plugin serves as a temporary solution, enabling the migration script for your site to give your plugin and theme authors some more time to update, and test, their code.
With the update to WordPress 5.6, the included version of jQuery is also upgraded. This means that old code that previously caused warnings now may instead may cause errors or stop working entirely.
Some of the features no longer working will just stop working behind the scenes without any apparent problem.
The plugin will let you downgrade to a previous version of jQuery for a period, but as a site administrator you are encouraged to get the underlying issue fixed.

Enable jQuery Migrate Helper

Also lets you know when it's no longer needed!!!!

This is what I call going above and beyond. I would rate 10 stars if I could. You deserve it.

Love it, super simple - perfect solution

Get information about calls to deprecated jQuery features in plugins or themes.

JavaScript Logic vs Enable jQuery Migrate Helper