I suggest you to apply temporary fix to avoid this issue. Our solution is more complicated.
Just edit file: modules/CRM/Roundcube/Roundcube_0.php
lines ~126 there is
foreach($emails as $email) {
$cc = Utils_RecordBrowserCommon::get_records('rc_mails',array('(~from'=>'%'.$email.'%','|~to'=>'%'.$email.'%'));
foreach($cc as $mail) {
add one line there:
foreach($emails as $email) {
if (!$email) continue; // add this line
$cc = Utils_RecordBrowserCommon::get_records('rc_mails',array('(~from'=>'%'.$email.'%','|~to'=>'%'.$email.'%'));
foreach($cc as $mail) {
Regards,
Adam
