Warning: Undefined property: Elementor\Plugin::$experiments in /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/themes/hello-elementor/includes/elementor-functions.php on line 226

Fatal error: Uncaught TypeError: method_exists(): Argument #1 ($object_or_class) must be of type object|string, null given in /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/themes/hello-elementor/includes/elementor-functions.php:226
Stack trace:
#0 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/themes/hello-elementor/includes/elementor-functions.php(226): method_exists(NULL, 'is_feature_acti...')
#1 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/themes/hello-elementor/includes/elementor-functions.php(14): hello_header_footer_experiment_active()
#2 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/class-wp-hook.php(287): hello_elementor_settings_init('')
#3 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#4 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/plugin.php(484): WP_Hook->do_action(Array)
#5 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/plugins/elementor/includes/plugin.php(524): do_action('elementor/init')
#6 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/class-wp-hook.php(287): Elementor\Plugin->init('')
#7 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters(NULL, Array)
#8 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-includes/plugin.php(484): WP_Hook->do_action(Array)
#9 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-settings.php(557): do_action('init')
#10 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-config.php(118): require_once('/customers/b/8/...')
#11 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-load.php(37): require_once('/customers/b/8/...')
#12 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-blog-header.php(13): require_once('/customers/b/8/...')
#13 /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/index.php(17): require('/customers/b/8/...')
#14 {main}
  thrown in /customers/b/8/0/biblekaj-kunstgalerie.ch/httpd.www/wp-content/themes/hello-elementor/includes/elementor-functions.php on line 226