In WordPress 5.5, the jQuery Migrate script was removed, and a new version of jQuery was introduced in WordPress 5.6. As a result, many themes and plugins were not prepared or updated, causing issues with websites.
During that time, the jQuery Migrate Helper plugin was installed on many websites to compensate for the missing jQuery Migrate functionality.
Fortunately, we have seen that many themes and plugins have made the necessary adjustments, rendering the temporary solution of the jQuery Migrate Helper plugin unnecessary.
If you have updated your themes and plugins, it is likely that you no longer need the jQuery Migrate Helper plugin and can remove it from your website.