PHP Fatal Error

I’m trying to upgrade my PHO version to v8.1 and running a SSH test with following command: /dh/cgi-system/php81.cgi index.php

I receive a Fatal PHP error as follow:

PHP Fatal error: Uncaught ArgumentCountError: Too few arguments to function WP_Widget::__construct(), 0 passed in /home/fw_live/fussballwitwe.de/wp-includes/class-wp-widget-factory.php on line 62 and at least 2 expected in /home/fw_live/fussballwitwe.de/wp-includes/class-wp-widget.php:163
Stack trace:

0 /home/fw_live/fussballwitwe.de/wp-includes/class-wp-widget-factory.php(62): WP_Widget->__construct()

1 /home/fw_live/fussballwitwe.de/wp-includes/widgets.php(123): WP_Widget_Factory->register(‘SlideshowPlugin…’)

2 /home/fw_live/fussballwitwe.de/wp-content/plugins/slideshow-jquery-image-gallery/classes/SlideshowPluginWidget.php(153): register_widget(‘SlideshowPlugin…’)

3 /home/fw_live/fussballwitwe.de/wp-includes/class-wp-hook.php(324): SlideshowPluginWidget::registerWidget(”)

4 /home/fw_live/fussballwitwe.de/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)

5 /home/fw_live/fussballwitwe.de/wp-includes/plugin.php(517): WP_Hook->do_action(Array)

6 /home/fw_live/fussballwitwe.de/wp-includes/widgets.php(1870): do_action(‘widgets_init’)

7 /home/fw_live/fussballwitwe.de/wp-includes/class-wp-hook.php(324): wp_widgets_init(”)

8 /home/fw_live/fussballwitwe.de/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)

I am just wondering why others haven;t reported anything like this and if it may be an error with my theme.

Thanks!

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