diff --git a/de.systopia.civiproxy/CRM/Civiproxy/Mailer.php b/de.systopia.civiproxy/CRM/Civiproxy/Mailer.php
index f62eb9e..15ed411 100644
--- a/de.systopia.civiproxy/CRM/Civiproxy/Mailer.php
+++ b/de.systopia.civiproxy/CRM/Civiproxy/Mailer.php
@@ -55,7 +55,8 @@ class CRM_Civiproxy_Mailer {
     // General external functions
     $value = preg_replace("#{$system_base}sites/all/modules/civicrm/extern/url.php#i",  $proxy_base.'/url.php',      $value);
     $value = preg_replace("#{$system_base}sites/all/modules/civicrm/extern/open.php#i", $proxy_base.'/open.php',     $value);
-    $value = preg_replace("#{$system_base}sites/default/files/civicrm/persist/#i",      $proxy_base.'/file.php?id=', $value);
+    $value = preg_replace("#{$system_base}sites/default/files/civicrm/persist/#i",      $proxy_base.'/file.php?mosaico=0&id=', $value);
+    $value = preg_replace("#{$system_base}civicrm/mosaico/img\?src=#i",                 $proxy_base.'/file.php?mosaico=1&id=', $value);
 
     // Mailing related functions
     $value = preg_replace("#{$system_base}civicrm/mailing/view#i",                      $proxy_base.'/mailing/mail.php', $value);
diff --git a/proxy/config.php b/proxy/config.php
index 8b09083..f18235a 100644
--- a/proxy/config.php
+++ b/proxy/config.php
@@ -30,6 +30,7 @@ $target_url       = $target_civicrm . '/sites/all/modules/civicrm/extern/url.php
 $target_open      = $target_civicrm . '/sites/all/modules/civicrm/extern/open.php';
 $target_file      = $target_civicrm . '/sites/default/files/civicrm/persist/';
 $target_mail_view = $target_civicrm . '/civicrm/mailing/view';
+$target_mosaico_file = $target_civicrm . '/civicrm/mosaico/img?src=';
 
 // Set api-key for mail subscribe/unsubscribe user
 // Set to NULL/FALSE to disable the feature
diff --git a/proxy/file.php b/proxy/file.php
index 36684dd..fa52084 100644
--- a/proxy/file.php
+++ b/proxy/file.php
@@ -6,20 +6,20 @@
 | Author: B. Endres (endres -at- systopia.de)             |
 | http://www.systopia.de/                                 |
 +---------------------------------------------------------*/
-
 require_once "config.php";
 require_once "proxy.php";
 
+// basic restraints
+$valid_parameters = array( 'id'   => 'string', 'mosaico'  => 'int' );
+$parameters = civiproxy_get_parameters($valid_parameters);
 // see if file caching is enabled
-if (!$target_file) civiproxy_http_error("Feature disabled", 405);
+if ((!$target_file && !$parameters['mosaico']) || (!$target_mosaico_file && $parameters['mosaico'])) {
+  civiproxy_http_error("Feature disabled", 405);
+}
 
 // basic check
 civiproxy_security_check('file');
 
-// basic restraints
-$valid_parameters = array( 'id'   => 'string' );
-$parameters = civiproxy_get_parameters($valid_parameters);
-
 // check if id specified
 if (empty($parameters['id'])) civiproxy_http_error("Resource not found");
 
@@ -66,9 +66,13 @@ if ($header && $data) {
   print $data;
   exit();
 }
-
 // if we get here, we have a cache miss => load
-$url = $target_file . $parameters['id'];
+if ($parameters['mosaico'] == 1) {
+  $url = $target_mosaico_file . $parameters['id'];
+}
+else {
+  $url = $target_file . $parameters['id'];
+}
 // error_log("CACHE MISS. LOADING $url");
 
 $curlSession = curl_init();
@@ -92,7 +96,6 @@ if (curl_error($curlSession)) {
   error_log(curl_error($curlSession));
   civiproxy_http_error(curl_error($curlSession), curl_errno($curlSession));
 }
-
 // process the results
 $content = explode("\r\n\r\n", $response, 2);
 $header  = $content[0];
@@ -101,6 +104,13 @@ $body    = $content[1];
 // extract headers
 $header_lines = explode(chr(10), $header);
 
+// Remove chunked encoding header
+foreach ($header_lines as $k => $header_line) {
+  if(strpos($header_line,'Transfer-Encoding: chunked') !== FALSE) {
+    unset($header_lines[$k]);
+  }
+}
+
 // store the information in the cache
 $file_cache->save(json_encode($header_lines), $header_key);
 $file_cache->save($body, $data_key);