Title: Polyfill.io
Last modified: May 1, 2020

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# Polyfill.io

 *  Resolved [michaelmartin73](https://wordpress.org/support/users/michaelmartin73/)
 * (@michaelmartin73)
 * [6 years, 1 month ago](https://wordpress.org/support/topic/polyfill-io/)
 * Hi Paul,
 * I hope you are well. I’ve been running tests on [https://www.webpagetest.org](https://www.webpagetest.org)
   for our site [https://reclaimdesign.org](https://reclaimdesign.org) and some 
   of the results pertain to:
 * Leverage browser caching of static assets: 88/100 Learn More
 * FAILED – (No max-age or expires) – [https://polyfill.io/v3/polyfill.min.js?features=Array.prototype.findIndex%2CCustomEvent%2CElement.prototype.closest%2CElement.prototype.dataset%2CEvent%2CXMLHttpRequest%2CMutationObserver&flags=gated&ver=5.4.1](https://polyfill.io/v3/polyfill.min.js?features=Array.prototype.findIndex%2CCustomEvent%2CElement.prototype.closest%2CElement.prototype.dataset%2CEvent%2CXMLHttpRequest%2CMutationObserver&flags=gated&ver=5.4.1)
 * Use a CDN for all static assets: 89/100
 * FAILED – [https://polyfill.io/v3/polyfill.min.js?features=Array.prototype.findIndex%2CCustomEvent%2CElement.prototype.closest%2CElement.prototype.dataset%2CEvent%2CXMLHttpRequest%2CMutationObserver&flags=gated&ver=5.4.1](https://polyfill.io/v3/polyfill.min.js?features=Array.prototype.findIndex%2CCustomEvent%2CElement.prototype.closest%2CElement.prototype.dataset%2CEvent%2CXMLHttpRequest%2CMutationObserver&flags=gated&ver=5.4.1)
 * Is polyfill associated with the site reviews plugin? If so, is it possible to
   resolve the above?
 * Thanks for your help.
 * Michael.

Viewing 1 replies (of 1 total)

 *  Plugin Author [Gemini Labs](https://wordpress.org/support/users/geminilabs/)
 * (@geminilabs)
 * [6 years, 1 month ago](https://wordpress.org/support/topic/polyfill-io/#post-12765273)
 * The polyfill.io script is used to provide JavaScript support for old unsupported
   browsers (i.e. Internet Explorer 11). The content of that file will be different
   depending on the web browser that is used.
 * To learn about how to leverage browser caching, please see: [https://robinroelofsen.com/browser-caching-htaccess-apache](https://robinroelofsen.com/browser-caching-htaccess-apache)

Viewing 1 replies (of 1 total)

The topic ‘Polyfill.io’ is closed to new replies.

 * ![](https://ps.w.org/site-reviews/assets/icon-256x256.gif?rev=3307009)
 * [Site Reviews](https://wordpress.org/plugins/site-reviews/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/site-reviews/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/site-reviews/)
 * [Active Topics](https://wordpress.org/support/plugin/site-reviews/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/site-reviews/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/site-reviews/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Gemini Labs](https://wordpress.org/support/users/geminilabs/)
 * Last activity: [6 years, 1 month ago](https://wordpress.org/support/topic/polyfill-io/#post-12765273)
 * Status: resolved