Hi,

As soon as I check the box “Page Cache” under “General Settings” -> “Debug”, I see the error:

.htaccess file contains rules to rewrite url https://www.mydomain.com/w3tc_rewrite_test into https://www.mydomain.com/?w3tc_rewrite_test which, if handled by plugin, return "OK" message.
The plugin made a request to https://www.mydomain.com/w3tc_rewrite_test but received: 
cURL error 60: SSL certificate problem: self signed certificate
instead of "OK" response. 

I hope someone knows what’s going on.