Only load the plugin when it is used on the page

I found a solution myself (I don’t know if it is clean but it seems to work).

It works in 2 steps:

In the main plugin file called “wp-social-bookmarking-light.php”, I changed the last lines (lines 52 to 60) :

// initialize
function wp_social_bookmarking_light_init()
{
    add_action('wp_head', 'wp_social_bookmarking_light_wp_head');
    add_action('wp_footer', 'wp_social_bookmarking_light_wp_footer');
    add_filter('the_content', 'wp_social_bookmarking_light_the_content');
    add_action('admin_menu', 'wp_social_bookmarking_light_admin_menu');
}
add_action( 'init', 'wp_social_bookmarking_light_init' );

to:

// initialize
function wp_social_bookmarking_light_init()
{
    add_action('admin_menu', 'wp_social_bookmarking_light_admin_menu');
}
add_action( 'init', 'wp_social_bookmarking_light_init' );

// enqueue scripts
function wp_social_bookmarking_light_enqueue_scripts()
{
    add_action('wp_head', 'wp_social_bookmarking_light_wp_head');
    add_action('wp_footer', 'wp_social_bookmarking_light_wp_footer');
    add_filter('the_content', 'wp_social_bookmarking_light_the_content');
}
add_action( 'wp_enqueue_scripts', 'wp_social_bookmarking_light_enqueue_scripts' );

With this change the action for the admin menu is still loaded on “init” but the other actions of the plugin are loaded on “wp_enqueue_scripts”.

Then in my “functions.php” file in my theme folder, I added the following lines:

function remove_wp_social_bookmarking_light() {
    if( ( !is_single() ) ) {
       remove_action( 'wp_enqueue_scripts', 'wp_social_bookmarking_light_enqueue_scripts' );
    }
}

add_action('template_redirect','remove_wp_social_bookmarking_light');

This code remove the WP Social Bookmarking Light scripts everywhere on the website except on single posts.