After the latest major WordPress 5.5 update, lots of websites are broken. The main issue is related to the fact the WordPress 5.5 removed the jQuery migrate.
Many old jQuery scripts present in the slider, menu, or other dynamic elements need to be updated for compatibility with the latest jQuery syntax and standards.
If you are using some custom jQuery code or older theme and plugin, this could be the cause of your website breaks after the latest update.
How to fix jQuery migrate problem after WordPress 5.5 update?
The solution to this issue should be simple.
Just access the WP admin -> Plugins -> Add new.
Here just type the “Enable jQuery migrate helper” in the search form at the right side and wait for the results.
Once the plugin is listed below, hit the install button and activate the plugin. See this image:
After you activate the Enable jQuery migrate plugin it will work automatically and no setup is necessary.
This is a Temporary Solution
We need to warn you that this solution is just temporary!
You should consider replacing the old jQuery scripts that are depending on this plugin. Make sure that you update your old themes and plugin in order to avoid future problems with jQuery and JavaScript.