Title: Uncaught ReferenceError: loadCSS is not defined
Last modified: December 21, 2018

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# Uncaught ReferenceError: loadCSS is not defined

 *  Resolved [JohnS0N](https://wordpress.org/support/users/johns0n/)
 * (@johns0n)
 * [7 years, 5 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-loadcss-is-not-defined/)
 * In the console, I get the above error on all the product pages by enabling your
   plugin. If I disable it, the error dissapears. Can you please solve the incompatibility
   as I think this is what is causing mobile friendly tests in google to fail and
   thus decrease serp rankings?
 * Thanks!
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Funcaught-referenceerror-loadcss-is-not-defined%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [Raul P.](https://wordpress.org/support/users/alignak/)
 * (@alignak)
 * [7 years, 5 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-loadcss-is-not-defined/#post-11020074)
 * The error you see, is precisely the function that defines LoadCSS… an exact copy
   from [https://github.com/filamentgroup/loadCSS](https://github.com/filamentgroup/loadCSS)
   so it’s not “undefined”.
 * I’m not sure how you are receiving that error, perhaps there is a conflict with
   one of the other javascript files you use.
 * loadCSS is merely an extra function that it’s there “if needed”, when you use
   some specific advanced settings to load some scripts async.
 * In your case, it’s not being in use by anything… it’s just there, in the footer.
   
   [http://prntscr.com/lycxtr](http://prntscr.com/lycxtr)
 * The next FVM version will stop loading this function if not in use, so wait for
   a couple of days.
 * Also, the mobile friendly tests failing is completely unrelated to that.
    If 
   you google about the tests failing, you will see a lot of complaints about it
   randomly failing the tests… it happens, because google doesn’t want to download
   too many resources in the page.
 * You can try testing some popular sites and see it fail… and it’s like that since
   at least 2015. Look at pagespeed insights test, because if there is something
   wrong and your site is not mobile friendly, it will let you know right away.
 *  Thread Starter [JohnS0N](https://wordpress.org/support/users/johns0n/)
 * (@johns0n)
 * [7 years, 5 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-loadcss-is-not-defined/#post-11021144)
 * Thank you very much for your very quick response Raul. Your plugin and support
   is helping thousands of people… that’s not a small number 🙂
 * You are right in that the function is not doing anything in my setup, so to remove
   the call to it if it’s not being used is highly appreaciated.
 * You are also right about the randomly failing tests. I suppose every little byte
   counts now… even though the page is quite light it seems it’s really hard to 
   lower the resources on a wordpress + woocommerce website without affecting user
   experience and functionality.
 * Plugins like yours make our work a lot more efficient since at least one part
   of the whole website management is taken care off with the help of such plugins.
 * Keep up the wonderful work.
 * P.S. Since you already mention pagespeed insights… If you test the above url 
   with it, you will see that somehow FVM doesn seem to pick up the css from alidswoo
   plugin, so it’s not combined and minified with FVM.
    -  This reply was modified 7 years, 5 months ago by [JohnS0N](https://wordpress.org/support/users/johns0n/).
    -  This reply was modified 7 years, 5 months ago by [JohnS0N](https://wordpress.org/support/users/johns0n/).

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Uncaught ReferenceError: loadCSS is not defined’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [JohnS0N](https://wordpress.org/support/users/johns0n/)
 * Last activity: [7 years, 5 months ago](https://wordpress.org/support/topic/uncaught-referenceerror-loadcss-is-not-defined/#post-11021144)
 * Status: resolved