Title: One css refuses to minify Last modified: October 2, 2026 --- # One css refuses to minify * [Clear Skies](https://wordpress.org/support/users/vavw/) * (@vavw) * [21 hours, 28 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/) * Hi, * A single css sheet refuses to minify. It did behave correctly up until a few weeks ago. * ../wp-content/plugins/ml-slider/assets/metaslider/public.css?ver=3.113.1 * Also posted on [https://wordpress.org/support/topic/metaslide-css-not-minifying-since-last-2-updates/#post-19034954](https://wordpress.org/support/topic/metaslide-css-not-minifying-since-last-2-updates/#post-19034954). This makes me believe the WP-Optimize is the culprit. Not a major bug, but I hope you can provide a fix. * Cheers, * Victor Viewing 6 replies - 1 through 6 (of 6 total) * Plugin Support [jbgupdraft](https://wordpress.org/support/users/jbgupdraft/) * (@jbgupdraft) * [21 hours, 17 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19034976) * Hi, * Thanks for reporting this! I’ve just installed Metaslider and on my test site the public.css file is being minified. * Can you take a look in WP-Optimize > Minify > CSS and let me know if there are any exclusions added there? * It might also be a good idea to temporarily deactivate other plugins aside from WP-Optimize and Metaslider to see if there’s something else conflicting. * Let me know about the exclusions and whether the plugin conflict test results in the file being minified successfully. * Thanks! * Thread Starter [Clear Skies](https://wordpress.org/support/users/vavw/) * (@vavw) * [20 hours, 55 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035002) * Thank you for your swift reply. * I have no exclusions. * Tested by switching off other plugins, then back on, but the issue seems to be with the [Metaslider Slideshow](https://www.metaslider.com/) plugin, only, and since a recent update of the plugin. * As noted in the other thread (link above), they did move assets from the header to the footer. I suspect this may be causing issues, as it is the same Metaslider plugin that is cause for more ‘requests’ than usual (AIOSEO’s SEO-analysis noting 22 – more than 20 – which is new, too), as well as an increase in size of the HTML document by approximately 30KB. * With the Metaslider plugin disabled, my website’s HTML document is 73KB and there are fewer than 20 requests. * With the plugin enabled, the size is 102KB with 22 requests and the _../wp-content/ plugins/ml-slider/assets/metaslider/public.css?ver=3.113.1_ file is not minimized. * Plugin Support [jbgupdraft](https://wordpress.org/support/users/jbgupdraft/) * (@jbgupdraft) * [20 hours, 46 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035014) * Hi, * Thanks so much for checking that. It definitely might be related to the change of the location of the public.css file but when I was testing it I did get that file minified and merged. I tested with and without the merging of the CSS files after minification but it worked for me in both cases. * Are there multiple slideshows on a given page? I had only tested with one but if your site has multiple per page I’ll test that out too on my end. * Thanks! * Thread Starter [Clear Skies](https://wordpress.org/support/users/vavw/) * (@vavw) * [20 hours, 3 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035072) * It has a bunch: [https://clearskies.eu](https://clearskies.eu), past the fold. * Plugin Support [jbgupdraft](https://wordpress.org/support/users/jbgupdraft/) * (@jbgupdraft) * [19 hours, 33 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035118) * Hi, * Thanks for sending that over. I’ve tested again on my site but I’m still getting the file minified by WP-Optimize. * One difference that I’m seeing though is on my site their public.css file is still loading in the header, whereas on your site it’s loading in the footer. * Would it be possible to temporarily switch to a default theme such as Twenty Twenty Five to see if the same behaviour is happening? * Thanks! * Thread Starter [Clear Skies](https://wordpress.org/support/users/vavw/) * (@vavw) * [29 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035562) * When switching to a default or non-child theme, the sliders are not displayed and the problem of non-minification does not manifest itself. It’s clear that the problem is only there when the sliders are displayed on the homepage. * In the mean time, the folks at Metaslider [are ensuring their css will be minified in their next release](https://wordpress.org/support/topic/metaslide-css-not-minifying-since-last-2-updates/#post-19035178), so that may fix it. Viewing 6 replies - 1 through 6 (of 6 total) You must be [logged in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fone-css-refuses-to-minify%2F%3Foutput_format%3Dmd&locale=en_US) to reply to this topic. * ![](https://ps.w.org/wp-optimize/assets/icon-256x256.png?rev=1552899) * [WP-Optimize – Cache, Compress images, Minify & Clean database to boost page speed & performance](https://wordpress.org/plugins/wp-optimize/) * [Frequently Asked Questions](https://wordpress.org/plugins/wp-optimize/#faq) * [Support Threads](https://wordpress.org/support/plugin/wp-optimize/) * [Active Topics](https://wordpress.org/support/plugin/wp-optimize/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/wp-optimize/unresolved/) * [Reviews](https://wordpress.org/support/plugin/wp-optimize/reviews/) * 6 replies * 2 participants * Last reply from: [Clear Skies](https://wordpress.org/support/users/vavw/) * Last activity: [29 minutes ago](https://wordpress.org/support/topic/one-css-refuses-to-minify/#post-19035562) * Status: not resolved