Check box email plugin for rounbcube

Introduction
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This is plugin for roundcube

Install
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Edit config/config.inc.php

1- Add the plugin to roundcube $config['plugins'] array like:

$config['plugins'] = array(
    'chbox',
    'archive',
    'zipdownload',
    'jqueryui',
    'filters',
    'userinfo',
    'password',
    'markasjunk2',
    'hide_blockquote',
    'contextmenu',
    'globaladdressbook',
    'newmail_notifier',
    'vcard_attachments',
);

2- Add 'chbox' column to $config['list_cols'] array like:

$config['list_cols'] = array('chbox','subject','status', 'from', 'date', 'size', 'flag', 'attachment','list_cols');

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[CODE TESTING]
Tested 24.05.2018 on Roundcube 1.1.12
Tested 28.05.2018 on Roundcube 1.0.12
Tested 28.05.2018 on Roundcube 1.2.7
Tested 28.05.2018 on Roundcube 1.3.4
Tested 24.07.2018 on Roundcube 1.3.6
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[TEST SERVER CONFIGURATION]
ubuntu 16.04 4.4.0-116-generic
Apache/2.4.18 (Ubuntu)
PHP 5.6.34-1+ubuntu16.04.1+deb.sury.org+1 (cli)
mysql  Ver 14.14 Distrib 5.7.21, for Linux (x86_64) using  EditLine wrapper
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[config.inc.php]
$config['default_host'] = 'ssl://imap.yandex.ru';
$config['imap_disabled_caps'] = array('BINARY');
$config['default_port'] = 993;
$config['smtp_server'] = 'ssl://smtp.yandex.ru';
$config['smtp_port'] = 465;
$config['plugins'] = array('filters','chbox');
$config['htmleditor'] = 0;
$config['smtp_user'] = '%u';
$config['smtp_pass'] = '%p';
$config['list_cols'] = array('chbox','subject','status', 'from', 'date', 'size', 'flag', 'attachment','list_cols');
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If you want the plugin to work in other skins, please send skin sources