Notice: Trying to access array offset on value of type null in /var/www/html/chamilo/main/inc/lib/api.lib.php on line 702

Question

I am now to linux and I need to install chamilo-lms. I have installed chamilo using:

• cd /tmp && wget https://github.com/chamilo/chamilo-lms/releases/download/v1.11.6/chamilo-1.11.6-php7.zip
• unzip chamilo-1.11.6-php7.zip

and php7.4

When I access the link for chamilo, I receive the following error, many times on the screen:

Notice: Trying to access array offset on value of type null in /var/www/html/chamilo/main/inc/lib/api.lib.php on line 702

In code, /var/www/html/chamilo/main/inc/lib/api.lib.php, it looks like this:

* Vchamilo changes : allow using an alternate configuration
* to get vchamilo  instance paths
*/
function api_get_path($path = '', $configuration = [])
{
    global $paths;

    // get proper configuration data if exists
    global $_configuration;

    $emptyConfigurationParam = false;
    if (empty($configuration)) {
        $configuration = (array) $_configuration;
        $emptyConfigurationParam = true;
    }

    $course_folder = 'courses/';
    static $root_web = '';
    $root_sys = $_configuration['root_sys'];

I can provide additional code if needed.

I was looking what to chance to code, but I could not find or understand in order to make it work.

Any help is very much appreciated.

Thank you, Gabriela