on further experimentation, i was wrong about the proxy setting having any effect on the plugin recognizing the HTTPS host as a subdomain. i hadn’t realized how much “cleaning up” i need to do to see the result of changing things clearly: clearing caches, saving settings, restarting the php-fpm process… anyway, now that i know all that, i can see that the proxy setting has no effect.
when i have the HTTP host proxied by cloudflare the plugin will not set a domain-wide cookie.
given that the HTTPS host is a simple subdomain of the HTTP host, i’m sure that there has to be a relatively simple fix for this. mike: is there anything that i can do to make it easy for you to diagnose? i can set up a user on my site and/or do any experiments that you want to suggest and log results.
i’m also willing to dig around in the plugin’s code and try things if you could point me in the direction of where to start. i’ve looked through it, and i write code, but not php and i have never done a wp plugin, so the whole structure is a little bewildering to me. i’m thinking that it has to be somewhere in the code that is validating the subdomain, but for the life of me i can’t imagine what difference it can make having the HTTP host proxied by cloudflare. it’s still the same URL, same hostname, same basename.