Fatal error: Uncaught Error: Cannot use object of type Closure as array

thanks for replay,
so to check if it is not related with any other plugins i made a clean wordpress instalation with only Your plugin and AMP plugin

this error occurs once You click View AMP -> Re-validate link in wp admin bar https://imgur.com/a/LhyXubO

WP Version: 5.1.1
PHP Version: 7.3
Other plugins: AMP plugin
Theme: Twenty sixteen

best regards

sorry @keraweb , i’ve haven’t seen that You replayed

steps to reproduce:
1. fresh wp install with just two – Your plugin and AMP
https://ww.wp.xz.cn/plugins/amp/
2. template mode – Standard or Transitional – both produced an error
3. theme – Twenty SixteenVersion: 2.0
4. go to home page and click in wp admin bar -> AMP->AMP revalidate( https://imgur.com/a/ttU5cLy )

stack trace:
PHP Fatal error: Uncaught Error: Cannot use object of type Closure as array in /var/www/html/wp-content/plugins/widget-css-classes/includes/widget-css-classes.class.php:747
Stack trace:
#0 /var/www/html/wp-content/plugins/widget-css-classes/includes/widget-css-classes.class.php(469): WCSSC::get_widget_opt(Array)
#1 /var/www/html/wp-content/plugins/amp/includes/validation/class-amp-validation-manager.php(1544): WCSSC::add_widget_classes(Array)
#2 /var/www/html/wp-content/plugins/amp/includes/validation/class-amp-validation-manager.php(1254): AMP_Validation_Manager::{closure}(Array)
#3 /var/www/html/wp-includes/class-wp-hook.php(286): AMP_Validation_Manager::{closure}(Array)
#4 /var/www/html/wp-includes/plugin.php(208): WP_Hook->apply_filters(Array, Array)
#5 /var/www/html/wp-includes/widgets.php(738): apply_filters(‘dynamic_sidebar…’, Array)
#6 /var/www/html/wp-content/themes/twentysixteen/sidebar.php(13): dynamic_sidebar(‘sidebar-1’)
#7 /var/www/html/wp-includes/template.php(722): require_once(‘/var/www/html/w…’)
#8 /var/ in /var/www/html/wp-content/plugins/widget-css-classes/includes/widget-css-classes.class.php on line 747

hope it helps 😉
best regards

it look like it does the trick, errors are gone 😉

thanks