[`php-mbstring`](http://php.net/manual/en/book.mbstring.php) | CentOS, Fedora, RHEL, Windows, some hosting providers | multibyte (Unicode) string support
[`php-gd`](http://php.net/manual/en/book.image.php) | optional | required to use thumbnails
[`php-intl`](http://php.net/manual/en/book.intl.php) | optional | localized text sorting (e.g. `e->è->f`)
[`php-mbstring`](http://php.net/manual/en/book.mbstring.php) | CentOS, Fedora, RHEL, Windows, some hosting providers | multibyte (Unicode) string support
[`php-gd`](http://php.net/manual/en/book.image.php) | optional | required to use thumbnails
[`php-intl`](http://php.net/manual/en/book.intl.php) | optional | localized text sorting (e.g. `e->è->f`)