papercite not working

I didn’t realize that papercite was not working when I moved my WordPress to a new server. It took me a long time to figure out what was wrong.

But once I figure out how to debug WordPress, it becomes very easy to fix the problem. To debug, add

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);

in wp_config.php

The response appears to be “real-time”. I don’t need to restart nginx. Then, I realize that just two PHP functions are not defined. It was solved after installing the missing packages.

sudo apt-get install php-mbstring

sudo apt-get install php-xml

Should restart nginx after installing missing packages by running

sudo service nginx restart