diff --git a/wp-mat.php b/wp-mat.php
index 650dd0029d066976ffb410d5330a23a2d949a7a8..8a03014667ae07524ef1c1875c59ed44ba1d5ecc 100644
--- a/wp-mat.php
+++ b/wp-mat.php
@@ -10,6 +10,10 @@
  * License URI: http://opensource.org/licenses/MIT
  */
 
+if (!defined("WP_MAT_ENDPOINT")) {
+    define("WP_MAT_ENDPOINT", "http://localhost:7111");
+}
+
 // Check if the mime type is one of those we want to clean up.
 function wp_mat_is_supported_mime_type($mimetype) {
     if (substr($mimetype, 0, 6) === "image/") {
@@ -46,11 +50,12 @@ function wp_mat_issue_request($path, $mimetype, $output_path) {
     return $ret;
 }
 
-function wp_mat_handle_upload_prefilter(&$file) {
+function wp_mat_handle_upload_prefilter($file) {
     if (isset($file['error'])) {
         return $file;
     }
     if (!wp_mat_is_supported_mime_type($file['type'])) {
+        error_log("wp-mat: unsupported mime type ".$file['type']);
         return $file;
     }