diff --git a/extension/Classes/Core/AbstractBuildForm.php b/extension/Classes/Core/AbstractBuildForm.php
index 28fe871a9502044176d0337be67c5e3158bee926..b92303163b3a1d7cbc53e7fe1552af9c3cc1e460 100644
--- a/extension/Classes/Core/AbstractBuildForm.php
+++ b/extension/Classes/Core/AbstractBuildForm.php
@@ -1531,6 +1531,11 @@ abstract class AbstractBuildForm {
             $formElement[FE_INPUT_TYPE] = 'number';
         }
 
+        // when size empty but value contains \n then set auto multi line
+        if (strpos($value, "\n") == true && empty($formElement[FE_SIZE])) {
+            $formElement[FE_SIZE]='50,2';
+        }
+
         // Check for input type 'textarea'. Possible notation: a) '', b) '<width>', c) '<width>,<height>', d) '<width>,<min-height>,<max-height>'
         $colsRows = explode(',', $formElement[FE_SIZE], 3);