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Page Speed Insights Ignores CloudFlare's Rocket Loader

See original GitHub issue

Cloudflare has a tool for website’s dubbed the Rocket Loader. Doc: https://support.cloudflare.com/hc/en-us/articles/200168056-What-does-Rocket-Loader-do-

The tool effectively will optimize the website by renaming all <script> related tags to something like the following.

<script src='/wp-includes/js/jquery/jquery.js' type="text/javascript"></script> to the following

<script src='/wp-includes/js/jquery/jquery.js?ver=1.12.4-wp' type="4906178bed34d3d402cc70b3-text/javascript"></script> It also rewrites inline scripts so the opening <script> tag is rewritten to something like: <script type="4906178bed34d3d402cc70b3-text/javascript"> The concept is quite simple all the JS on the page is effectively deferred including inline JS. This is particularly useful when an application has an in-line script that is dependent on another file loading in a render-blocking fashion.

However, Page Speed Insights ignores this completely.

For instance on my domain: https://www.sertmedia.com/

You can run a test using Page Speed Insights and it will get flagged as JQuery being render-blocking.

However, if you run the same test in Lighthouse (on Chrome Canary)

It is properly detected as no longer being render-blocking. The issue, of course, is this can have a fairly drastic impact on performance between lighthouse local and page speed insights. Also, I tested the site on web.dev as well just for reference and it acts the same as page speed insights.