Slow SQL queries

Upon activation of Query Monitor, noticed a couple of slow queries all over the back-end coming from this plugin. The fix that worked for me is to limit calls of those queries only when using the plugin.

plugins\delete-thumbnails\delete-thumbnails.php line 16:

Change this:

function dlthumbs() {
	global $dlthumbs;
	if (is_admin()) // admin only
		$dlthumbs = new dlthumbs();
}

To this:

function dlthumbs() {
	global $dlthumbs, $pagenow;
	//ensure slow db calls aren't called everywhere in back-end 
	if ( is_admin() && $pagenow == 'tools.php' && isset( $_GET['page'] ) && $_GET['page'] == 'dlthumbs' ) {
		$dlthumbs = new dlthumbs();
	}
}