Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, class "WP_Duotone" not found in /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/class-wp-hook.php:308
Stack trace:
#0 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/plugin.php(205): WP_Hook->apply_filters(Array, Array)
#1 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/blocks.php(503): apply_filters('block_type_meta...', Array, Array)
#2 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/blocks/legacy-widget.php(62): register_block_type_from_metadata('/data/4/0/113/1...', Array)
#3 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/class-wp-hook.php(308): register_block_core_legacy_widget('')
#4 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)
#5 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#6 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-settings.php(623): do_action('init')
#7 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-config.php(87): require_once('/data/4/0/113/1...')
#8 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-load.php(50): require_once('/data/4/0/113/1...')
#9 /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-blog-header.php(13): require_once('/data/4/0/113/1...')
#10 /data/4/0/113/120/276446/user/280739/htdocs/examples/index.php(17): require('/data/4/0/113/1...')
#11 {main}
thrown in /data/4/0/113/120/276446/user/280739/htdocs/examples/wp-includes/class-wp-hook.php on line 308