Fatal error: Uncaught Error: Class "DOMDocument" not found
in /home/harmonicatabs.net/public_html/wp-content/plugins/w3speedster-wp/includes/class_init.php on line 737

Call stack:

1. W3speedster\w3speedster::w3ParseLink()
   wp-content/plugins/w3speedster-wp/includes/class_js_minify.php:140
2. W3speedster\w3speedster_js::minify()
   wp-content/plugins/w3speedster-wp/includes/class_html_optimize.php:137

Warning: Undefined array key "file" in /home/harmonicatabs.net/public_html/wp-content/plugins/query-monitor/collectors/php_errors.php on line 364

Warning: Undefined array key "line" in /home/harmonicatabs.net/public_html/wp-content/plugins/query-monitor/collectors/php_errors.php on line 364

3. W3speedster\w3speed_html_optimize::w3Speedster()
4. ob_end_flush()
   wp-includes/functions.php:5427
5. wp_ob_end_flush_all()
   wp-includes/class-wp-hook.php:324
6. WP_Hook::apply_filters()
   wp-includes/class-wp-hook.php:348
7. WP_Hook::do_action()
   wp-includes/plugin.php:517
8. do_action()
   wp-includes/load.php:1280

Warning: Undefined array key "file" in /home/harmonicatabs.net/public_html/wp-content/plugins/query-monitor/collectors/php_errors.php on line 364

Warning: Undefined array key "line" in /home/harmonicatabs.net/public_html/wp-content/plugins/query-monitor/collectors/php_errors.php on line 364

9. shutdown_action_hook()