Redirection has bad effects

Hello,

I see that when I configure WP Fastest Cache, this instructions are set in the top of .htaccess:

RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} ^www.longhu.es [NC]
RewriteRule ^(.*)$ http\:\/\/longhu\.es\/$1 [R=301,L]

As far as I understand, it redirects the www version to non-www version.

I have a link in my web to http://www.mydomain.es/moodle and it has to take the “www” (if not, moodle does not work). I had to remove WP Fastest Caché to be able to go to the moodle.

Is it necessary that redirection?
Can I make something to be able to go to http://www.mydomain.es/moodle (with www).

Thank you in advance.