Unusual high query of user meta data

I’m sure there are more sophisticated ways to debug the queries, but I’m not aware of them. So usually when I need to debug WP queries I use either Query Monitor or Debug Bar (with Slow Actions addon) plugin, which can be found on the wordpress.org plugin repository. These plugins help you trace which functions / plugins are slowing the site down. At least for me these plugins have been great help.

I’m not affiliated to any of these plugins and my apologies for giving just a plugin recommendation answer.