public static function clear_on_theme_changes()
 {
     static $once = false;
     /* Only clear once. */
     global $pagenow;
     /* Holds the current page filename. */
     global $current_site, $current_blog;
     /* Need these for Multisite details. */
     /**/
     do_action("ws_plugin__qcache_before_clear_on_theme_changes", get_defined_vars());
     /**/
     if (c_ws_plugin__qcache_utils_conds::is_blog_admin() && in_array($pagenow, $pages = array("themes.php"))) {
         if (!$once && ($once = true)) {
             if (is_multisite() && is_object($current_blog) && $current_blog->blog_id) {
                 c_ws_plugin__qcache_purging_routines::schedule_cache_dir_purge($current_blog);
                 /**/
                 if (!is_multisite() || !c_ws_plugin__qcache_utils_conds::is_multisite_farm() || is_main_site()) {
                     $notice = 'Blog# <code>' . esc_html($current_blog->blog_id) . '</code> : Quick Cache reset automatically to avoid conflicts :-)';
                     c_ws_plugin__qcache_admin_notices::enqueue_admin_notice($notice, $pages);
                 }
             } else {
                 c_ws_plugin__qcache_purging_routines::schedule_cache_dir_purge();
                 /**/
                 if (!is_multisite() || !c_ws_plugin__qcache_utils_conds::is_multisite_farm() || is_main_site()) {
                     $notice = 'Quick Cache reset automatically to avoid conflicts :-)';
                     c_ws_plugin__qcache_admin_notices::enqueue_admin_notice($notice, $pages);
                 }
             }
             /**/
             do_action("ws_plugin__qcache_during_clear_on_theme_changes", get_defined_vars());
         }
     }
     /**/
     do_action("ws_plugin__qcache_after_clear_on_theme_changes", get_defined_vars());
     /**/
     return;
     /* Return for uniformity. */
 }