unsquare

Thanks to the suggestion to deactivate Jetpack Notifications in one of the other threads about this issue, I was able to resolve the problem as follows:

1. Rename the Jetpack plugin folder from FTP to deactivate the plugin.
2. Access the WordPress admin Dashboard.
3. Change the Jetpack plugin folder back to the original name in FTP.
3. Reactivate the Jetpack plugin.
4. Go directly to the Jetpack modules page at wp-admin/admin.php?page=jetpack_modules and deactivate the Notifications module.

After taking those steps, my site loads as normal.

• This reply was modified 2 years, 2 months ago by unsquare.

Also, I’m using Plesk hosted on Amazon Lightsail.

This should do the trick:
https://codex.www.ads-software.com/Function_Reference/remove_theme_support

// in your Child Theme's functions.php    

// Use the after_setup_theme hook with a priority of 11 to load after the
// parent theme, which will fire on the default priority of 10
add_action( 'after_setup_theme', 'remove_featured_images_from_child_theme', 11 ); 

function remove_featured_images_from_child_theme() {

    // This will remove support for post thumbnails on ALL Post Types
    remove_theme_support( 'post-thumbnails' );

    // Add this line in to re-enable support at your chosen size
    add_theme_support( 'post-thumbnails' );
    set_post_thumbnail_size( 825, 0, true );
}