IMAP plugin not listing emails. requirements?

What are the requirements for IMAP plugin?

Auth is fine, IMAP folders are listed, but contents of folders appear empty.

Here is what i have


pydio-core-8.2.1.zip

php7-phar
php7-json
php7-openssl
php7-ctype
php7-curl
php7-dom
php7-mbstring
php7-pdo
php7-pdo_sqlite
php7-simplexml
php7-sqlite3
php7-tokenizer
php7-xml
php7-xmlwriter
php7-zip
php7-fpm
php7-mysqlnd
php7-mysqli
php7-gd
php7-intl
php7-opcache
php7-session
php7-memcached
php7-exif
php7-iconv
php7-imap
php7-ssh2
php7-pear
php7-pear-mail_mime
php7-pear-net_socket
php7-pear-net_smtp
php7-fileinfo
php7-mcrypt
php7-xsl
php7-xmlrpc
php7-pspell
php7-snmp

#pear list
INSTALLED PACKAGES, CHANNEL PEAR.PHP.NET:
=========================================
PACKAGE          VERSION STATE
Archive_Tar      1.4.3   stable
Console_Getopt   1.4.1   stable
MIME_Type        1.4.1   stable
Mail_Mime        1.10.2  stable
Mail_mimeDecode  1.5.6   stable
PEAR             1.10.6  stable
Structures_Graph 1.1.1   stable
XML_Util         1.4.2   stable

Am i missing anything?