diff --git a/extension/Classes/Core/Save.php b/extension/Classes/Core/Save.php
index ca3a758e977d317260cdf51dff50aef98a57d8fc..5e9cca3c8139ef44797e325ffb5213fd8bc40255 100644
--- a/extension/Classes/Core/Save.php
+++ b/extension/Classes/Core/Save.php
@@ -542,7 +542,9 @@ class Save {
             $vars[VAR_FILE_MIME_TYPE] = $statusUpload[FILES_TYPE] ?? '';
 
             // Check for 'unzip'.
-            if (isset($formElement[FE_FILE_UNZIP]) && $formElement[FE_FILE_UNZIP] != '0' && $vars[VAR_FILE_MIME_TYPE] = 'application/zip') {
+            if (isset($formElement[FE_FILE_UNZIP])
+                && $formElement[FE_FILE_UNZIP] != '0'
+                && $vars[VAR_FILE_MIME_TYPE] == 'application/zip') {
                 $flagDoUnzip = true;
             }