Fatal Error

Hello,

I am getting a fatal error on lessons pages :

Fatal error: Uncaught Error: Call to undefined function TUTOR\wp_enqueue_editor() in /var/www/clients/client5/web8/web/wp-content/plugins/tutor/classes/Assets.php:71 Stack trace: #0 /var/www/clients/client5/web8/web/wp-includes/class-wp-hook.php(298): TUTOR\Assets->frontend_scripts('') #1 /var/www/clients/client5/web8/web/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #2 /var/www/clients/client5/web8/web/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /var/www/clients/client5/web8/web/wp-includes/script-loader.php(1225): do_action('wp_enqueue_scri...') #4 /var/www/clients/client5/web8/web/wp-includes/class-wp-hook.php(298): wp_enqueue_scripts('') #5 /var/www/clients/client5/web8/web/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #6 /var/www/clients/client5/web8/web/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #7 /var/www/clients/client5/web8/web/wp-includes/general-template.php(2574): do_action('wp_head') #8 /var/www/clients/client5/web8/web/wp-content/ in /var/www/clients/client5/web8/web/wp-content/plugins/tutor/classes/Assets.php on line 71

Here is my configuration :

WordPress version: 4.7.13 – There is a newer version of WordPress available (5.6)
Tutor Version: 1.7.8
WordPress multisite: yes
WordPress memory limit: 512 MB
WordPress debug mode:
WordPress cron:
Language: fr_FR
External object cache: –
Server environment
Server info: Apache/2.4.25 (Debian)
PHP version: 7.0.30-0+deb9u1 – We recommend using PHP version 7.2 or above for greater performance and security.