diff --git a/CHANGELOG b/CHANGELOG
index 3d814b960..9bfb6d7e2 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -29,6 +29,8 @@ CHANGELOG Roundcube Webmail
 - Fix recipient duplicates in print-view when the recipient list has been expanded (#7169)
 - Fix bug where files in skins/ directory were listed on skins list (#7180)
 - Fix bug where message parts with no Content-Disposition header and no name were not listed on attachments list (#7117)
+- Fix display issues with mail subject that contains line-breaks (#7191)
+- Fix invalid Content-Transfer-Encoding on multipart messages - Mail_Mime fix (#7170)
 
 RELEASE 1.4.2
 -------------
diff --git a/program/lib/Roundcube/rcube.php b/program/lib/Roundcube/rcube.php
index 4bfe2d2bc..55340a6c1 100644
--- a/program/lib/Roundcube/rcube.php
+++ b/program/lib/Roundcube/rcube.php
@@ -1129,6 +1129,19 @@ class rcube
         return rcube_utils::rep_specialchars_output($str, 'js');
     }
 
+    /**
+     * Quote a given string, remove new-line characters, use strict mode.
+     * Shortcut function for rcube_utils::rep_specialchars_output()
+     *
+     * @param string $str A string to quote
+     *
+     * @return string HTML-quoted string
+     */
+    public static function SQ($str)
+    {
+        return rcube_utils::rep_specialchars_output($str, 'html', 'strict', false);
+    }
+
     /**
      * Construct shell command, execute it and return output as string.
      * Keywords {keyword} are replaced with arguments
diff --git a/program/lib/Roundcube/rcube_message.php b/program/lib/Roundcube/rcube_message.php
index e28672a2d..73ca59580 100644
--- a/program/lib/Roundcube/rcube_message.php
+++ b/program/lib/Roundcube/rcube_message.php
@@ -124,7 +124,7 @@ class rcube_message
         }
 
         $this->mime    = new rcube_mime($this->headers->charset);
-        $this->subject = $this->headers->get('subject');
+        $this->subject = str_replace("\n", '', $this->headers->get('subject'));
         $from          = $this->mime->decode_address_list($this->headers->from, 1);
         $this->sender  = current($from);
 
diff --git a/program/steps/mail/func.inc b/program/steps/mail/func.inc
index 4e2aa0799..799788135 100644
--- a/program/steps/mail/func.inc
+++ b/program/steps/mail/func.inc
@@ -510,7 +510,7 @@ function rcmail_js_message_list($a_headers, $insert_top=false, $a_show_cols=null
             else if ($col == 'subject') {
                 $cont = trim(rcube_mime::decode_header($header->$col, $header->charset));
                 if (!$cont) $cont = $RCMAIL->gettext('nosubject');
-                $cont = rcube::Q($cont);
+                $cont = rcube::SQ($cont);
             }
             else if ($col == 'size')
                 $cont = $RCMAIL->show_bytes($header->$col);
@@ -523,10 +523,10 @@ function rcmail_js_message_list($a_headers, $insert_top=false, $a_show_cols=null
                     $last_folder_name = str_replace($delimiter, " \xC2\xBB ", $last_folder_name);
                 }
 
-                $cont = rcube::Q($last_folder_name);
+                $cont = rcube::SQ($last_folder_name);
             }
             else
-                $cont = rcube::Q($header->$col);
+                $cont = rcube::SQ($header->$col);
 
             $a_msg_cols[$col] = $cont;
         }
@@ -1308,7 +1308,7 @@ function rcmail_address_string($input, $max=null, $linked=false, $addicon=null,
         $mailto = rcube_utils::idn_to_utf8($mailto);
 
         if ($PRINT_MODE) {
-            $address = sprintf('%s <%s>', rcube::Q($name), rcube::Q($mailto));
+            $address = sprintf('%s <%s>', rcube::SQ($name), rcube::Q($mailto));
         }
         else if ($valid) {
             if ($linked) {
@@ -1320,10 +1320,10 @@ function rcmail_address_string($input, $max=null, $linked=false, $addicon=null,
                 );
 
                 if ($show_email && $name && $mailto) {
-                    $content = rcube::Q($name ? sprintf('%s <%s>', $name, $mailto) : $mailto);
+                    $content = rcube::SQ($name ? sprintf('%s <%s>', $name, $mailto) : $mailto);
                 }
                 else {
-                    $content = rcube::Q($name ?: $mailto);
+                    $content = rcube::SQ($name ?: $mailto);
                     $attrs['title'] = $mailto;
                 }
 
@@ -1331,7 +1331,7 @@ function rcmail_address_string($input, $max=null, $linked=false, $addicon=null,
             }
             else {
                 $address = html::span(array('title' => $mailto, 'class' => "rcmContactAddress"),
-                    rcube::Q($name ?: $mailto));
+                    rcube::SQ($name ?: $mailto));
             }
 
             if ($addicon && $_SESSION['writeable_abook']) {
diff --git a/program/steps/mail/show.inc b/program/steps/mail/show.inc
index 03a26585a..546758a00 100644
--- a/program/steps/mail/show.inc
+++ b/program/steps/mail/show.inc
@@ -494,16 +494,16 @@ function rcmail_message_headers($attrib, $headers=null)
     // single header value is requested
     if (!empty($attrib['valueof'])) {
         $row = $plugin['output'][$attrib['valueof']];
-        return $row['html'] ? $row['value'] : rcube::Q($row['value']);
+        return $row['html'] ? $row['value'] : rcube::SQ($row['value']);
     }
 
     // compose html table
     $table = new html_table(array('cols' => 2));
 
     foreach ($plugin['output'] as $hkey => $row) {
-        $val = $row['html'] ? $row['value'] : rcube::Q($row['value']);
+        $val = $row['html'] ? $row['value'] : rcube::SQ($row['value']);
 
-        $table->add(array('class' => 'header-title'), rcube::Q($row['title']));
+        $table->add(array('class' => 'header-title'), rcube::SQ($row['title']));
         $table->add(array('class' => 'header '.$hkey), $val);
     }