PHP 8.0 errors

Hi Matt

Got the annual update PHP version for several clients. Updating to 7.4 is no problem, but 8.0+ results in a critical error:

Fatal error: Uncaught ArgumentCountError: Too few arguments to function WP_Widget::__construct(), 0 passed in /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-widget-factory.php on line 61 and at least 2 expected in /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-widget.php:162 Stack trace: #0 /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-widget-factory.php(61): WP_Widget->__construct() #1 /homepages/42/d686562318/htdocs/14/wp-includes/widgets.php(115): WP_Widget_Factory->register(‘GigCalendarWidg…’) #2 /homepages/42/d686562318/htdocs/14/wp-content/plugins/mf-gig-calendar/mf_gig_calendar_widget.php(157): register_widget(‘GigCalendarWidg…’) #3 /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-hook.php(303): GigCalendarWidgetInit(”) #4 /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array) #5 /homepages/42/d686562318/htdocs/14/wp-includes/plugin.php(470): WP_Hook->do_action(Array) #6 /homepages/42/d686562318/htdocs/14/wp-includes/widgets.php(1809): do_action(‘widgets_init’) #7 /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-hook.php(303): wp_widgets_init(”) #8 /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters(NULL, Array) #9 /homepages/42/d686562318/htdocs/14/wp-includes/plugin.php(470): WP_Hook->do_action(Array) #10 /homepages/42/d686562318/htdocs/14/wp-settings.php(578): do_action(‘init’) #11 /homepages/42/d686562318/htdocs/14/wp-config.php(92): require_once(‘/homepages/42/d…’) #12 /homepages/42/d686562318/htdocs/14/wp-load.php(50): require_once(‘/homepages/42/d…’) #13 /homepages/42/d686562318/htdocs/14/wp-blog-header.php(13): require_once(‘/homepages/42/d…’) #14 /homepages/42/d686562318/htdocs/14/index.php(17): require(‘/homepages/42/d…’) #15 {main} thrown in /homepages/42/d686562318/htdocs/14/wp-includes/class-wp-widget.php on line 162

There has been a critical error on this website.

Any ideas?

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