--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/program/steps/addressbook/mailto.inc	Thu Jan 04 15:52:31 2018 -0500
@@ -0,0 +1,76 @@
+<?php
+
+/**
+ +-----------------------------------------------------------------------+
+ | program/steps/addressbook/mailto.inc                                  |
+ |                                                                       |
+ | This file is part of the Roundcube Webmail client                     |
+ | Copyright (C) 2007-2013, The Roundcube Dev Team                       |
+ |                                                                       |
+ | Licensed under the GNU General Public License version 3 or            |
+ | any later version with exceptions for skins & plugins.                |
+ | See the README file for a full license statement.                     |
+ |                                                                       |
+ | PURPOSE:                                                              |
+ |   Compose a recipient list with all selected contacts                 |
+ |                                                                       |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com>                        |
+ +-----------------------------------------------------------------------+
+*/
+
+$cids    = rcmail_get_cids();
+$mailto  = array();
+$sources = array();
+
+foreach ($cids as $source => $cid) {
+    $CONTACTS = $RCMAIL->get_address_book($source);
+
+    if ($CONTACTS->ready) {
+        $CONTACTS->set_page(1);
+        $CONTACTS->set_pagesize(count($cid) + 2); // +2 to skip counting query
+        $sources[] = $CONTACTS->search($CONTACTS->primary_key, $cid, 0, true, true, 'email');
+    }
+}
+
+if (!empty($_REQUEST['_gid']) && isset($_REQUEST['_source'])) {
+    $source   = rcube_utils::get_input_value('_source', rcube_utils::INPUT_GP);
+    $group_id = rcube_utils::get_input_value('_gid', rcube_utils::INPUT_GP);
+
+    $CONTACTS   = $RCMAIL->get_address_book($source);
+    $group_data = $CONTACTS->get_group($group_id);
+
+    // group has an email address assigned: use that
+    if ($group_data['email']) {
+        $mailto[] = format_email_recipient($group_data['email'][0], $group_data['name']);
+    }
+    else if ($CONTACTS->ready) {
+        $CONTACTS->set_group($group_id);
+        $CONTACTS->set_page(1);
+        $CONTACTS->set_pagesize(200); // limit somehow
+        $sources[] = $CONTACTS->list_records();
+    }
+}
+
+foreach ($sources as $source) {
+    while (is_object($source) && ($rec = $source->iterate())) {
+        $emails = $CONTACTS->get_col_values('email', $rec, true);
+
+        if (!empty($emails)) {
+            $mailto[] = format_email_recipient($emails[0], $rec['name']);
+        }
+    }
+}
+
+if (!empty($mailto)) {
+    $mailto_str = join(', ', $mailto);
+    $mailto_id  = substr(md5($mailto_str), 0, 16);
+    $_SESSION['mailto'][$mailto_id] = urlencode($mailto_str);
+    $OUTPUT->command('open_compose_step', array('_mailto' => $mailto_id));
+}
+else {
+    $OUTPUT->show_message('nocontactsfound', 'warning');
+}
+
+// send response
+$OUTPUT->send();