Hi https://theme.co/forum/u/marc_a ,
It may (or may not) have been caused by CDN & Cache plugin misconfigurations / conflicts. I was experimenting with a combined use of Cloudflare CDN plugin, Litespeed Cache plugin and WP Cloudflare Super Page Cache plugin - as per the instructions in this article: https://webspeedtools.com/litespeed-cache-cloudflare/ . The problem started during use or after I uninstalled these plugins - I don’t exactly recall. i also use The “Site Kit” plugin by Google which bundle Analytics, Page Speed, Search Console etc services by Google. The Page Speed in the “Site Kit” plugin was showing the above mentioned error. Page Speed Insights in Google Developer site was also showing the same error - since the last day or two. I re-installed the main Clouflare CDN plugin and WP Cloudflare Super Page Cache plugin a little while ago and since then Page Speed Insights in Google Developer site started to work albeit giving a VERY VERY LOW performance score. But the Page Speed inside the Site Kit plugin still kept showing the error message!
I have followed the first two troubleshooting procedures so far that you have recommended. In fact I started with disabling even Cornerstone - along with all others and switching to Wordpress Twenty-Twenty One theme. That gave me a performance score of 93 in Page Speed Insights in Google Developer site. Then I activated Cornerstone ( along with X Child Theme) - which lowered my performance score quite a bit in Page Speed Insights in Google Developer site . Then I re-installed the Cloudflare CDN along with the WP Cloudflare Super Page Cache plugin (without enabling the ‘cache’ option in it). This brought my score in the outside PageSpeed to somewhere between 63-66. Then I re-installed Site Kit plugin again. This lowered my performance score in external Page Speed to 40. Then I UN-INSTALLED Site-Kit once again. Right away the performance score in external Page Speed scan from Google developer site shot up to 69 from 40!!
DURING NONE OF THESE TESTING THE PAGE-SPEED SCAN FROM INSIDE THE SITE-KIT PLUGIN WORKED – AND IT CONSISTENTLY KEPT SHOWING THE AFOREMENTIONED ERROR!!
I haven’t carried out the last 3 troubleshooting procedures you mentioned, but to me it looks like there is something wrong with the Site-Kit plugin itself. Maybe this is the main culprit - at least along with something else! What do you think???
Do you think I need to carry out the other troubleshooting steps any longer or just re-install Site-Kit or switch to another similar pluging? What do you think I should do now?