Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, non-static method wp_custom_sidebar_plugin::custom_sidebar_default_entry() cannot be called statically in /home/4/w/whitejoy/www/wp-includes/class-wp-hook.php:308 Stack trace: #0 /home/4/w/whitejoy/www/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array) #1 /home/4/w/whitejoy/www/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #2 /home/4/w/whitejoy/www/wp-settings.php(480): do_action('plugins_loaded') #3 /home/4/w/whitejoy/www/wp-config.php(90): require_once('/home/4/w/white...') #4 /home/4/w/whitejoy/www/wp-load.php(50): require_once('/home/4/w/white...') #5 /home/4/w/whitejoy/www/wp-blog-header.php(13): require_once('/home/4/w/white...') #6 /home/4/w/whitejoy/www/index.php(17): require('/home/4/w/white...') #7 {main} thrown in /home/4/w/whitejoy/www/wp-includes/class-wp-hook.php on line 308