Fatal error: Uncaught ArgumentCountError: Too few arguments to function WP_Widget::__construct(), 0 passed in /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-widget-factory.php on line 62 and at least 2 expected in /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-widget.php:163
Stack trace:
#0 /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-widget-factory.php(62): WP_Widget->__construct()
#1 /customers/2/b/3/esjm.be/httpd.www/wp-includes/widgets.php(115): WP_Widget_Factory->register('mts_ad_300_Widg...')
#2 /customers/2/b/3/esjm.be/httpd.www/wp-content/themes/esjm/functions/widget-ad300.php(17): register_widget('mts_ad_300_Widg...')
#3 /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-hook.php(308): mts_ad_300_widgets('')
#4 /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)
#5 /customers/2/b/3/esjm.be/httpd.www/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#6 /customers/2/b/3/esjm.be/httpd.www/wp-includes/widgets.php(1854): do_action('widgets_init')
#7 /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-hook.php(308): wp_widgets_init('')
#8 /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)
#9 /customers/2/b/3/esjm.be/httpd.www/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#10 /customers/2/b/3/esjm.be/httpd.www/wp-settings.php(617): do_action('init')
#11 /customers/2/b/3/esjm.be/httpd.www/wp-config.php(89): require_once('/customers/2/b/...')
#12 /customers/2/b/3/esjm.be/httpd.www/wp-load.php(50): require_once('/customers/2/b/...')
#13 /customers/2/b/3/esjm.be/httpd.www/wp-blog-header.php(13): require_once('/customers/2/b/...')
#14 /customers/2/b/3/esjm.be/httpd.www/index.php(17): require('/customers/2/b/...')
#15 {main}
  thrown in /customers/2/b/3/esjm.be/httpd.www/wp-includes/class-wp-widget.php on line 163