So, I upgraded my PhpStorm to 2019.1, and upgraded my PHP from 7.1 to 7.3, and added the following to the cli's php.ini:
Unfortunately, I can't validate the debugger. Even though $ php --version confirms I'm running 2.7.0, when I try to validate, I get the following:
It's a Symfony project, which is why I'm pointing it to the /path/to/project/web directory. And I can verify that everything is accessible at that URL since I can view my work in progress through the browser.
I'm not sure what else to do. It doesn't seem like PhpStorm is even aware that my browser is trying to engage remote debugging, and there's a complete lack of notification (beyond being unable to validate Xdebug) why. I've restarted my server, verified that my Xdebug php.ini values are in the phpinfo() output, etc. I'm stuck.