Autoptimize is a plugin that makes optimizing your site easy. It can aggregate, minify and cache scripts and styles. You can also optimize and lazy-load images
This guide has tips for troubleshooting issues if you are using MetaSlider with the Autoptimize plugin. These tips are not guaranteed to work, but will help with many common issues.
If you are using the Autoptimize plugin on your site and the slideshow is not updating, check the “Page Cache” settings. Try disabling the cache or skipping any pages with a slideshow.
If you are using the Autoptimize plugin on your site and the slideshow is not loading correctly, check the “JS, CSS, and HTML” settings. Try excluding these CSS files in the “Exclude scripts from Autoptimize” box.
/wp-content/plugins/ml-slider/assets/sliders/flexslider/flexslider.css/wp-content/plugins/ml-slider/assets/metaslider/public.css
And also try excluding these Javascript files in other “Exclude scripts from Autoptimize:” box.
/wp-content/plugins/ml-slider/assets/metaslider/script.min.js/wp-content/plugins/ml-slider/assets/easing/jQuery.easing.min.js
/wp-content/plugins/ml-slider/assets/sliders/flexslider/jquery.flexslider.min.js