Go to /etc/apache2/conf-available/javascript-common.conf
, you will find this:
Alias /javascript /usr/share/javascript/ <Directory "/usr/share/javascript/"> Options FollowSymLinks MultiViews </Directory>
So you just have to comment this lines (with the # char) (is not recommend to edit directly the file in conf-enabled) to avoid the forbidden error. After that, do this:
a2disconf javascript-common a2enconf javascript-common
References
https://serverfault.com/questions/274254/cannot-access-javascript-folder