How to find source of these strange SQL queries?

They’re from WordPress. They come from the wp_old_slug_redirect() function which is run whenever there is a 404. The purpose is to check if the requested URL was the old URL for a post so that it can redirect to the new URL. If you’re seeing a lot of these then it means you’re getting a … Read more

wp_mail function not working in user query loop

It’s possible that there’s an issue with your SMTP configuration or with the mailing queue. You can try using a debugging plugin, such as WP Mail Logging, to help diagnose the issue. This plugin logs all emails sent through WordPress and displays them in the admin dashboard, allowing you to see if the emails are … Read more