Fixed
I have fix problem (tested Field Editor VirtueMart 3.2.4 in Joomla 3.8.0 - 3.8.1 and 3.8.2 is ok )
Now edit file: administrator\components\com_virtuemart\models\customfields.php
Find row: //'X'=>'COM_VIRTUEMART_CUSTOM_EDITOR', and code bellow (line 740: )
customfield_value . '</textarea>
<script type="text/javascript">// Creates a new editor instance
tinymce.execCommand("mceAddControl",true,"field-' . $row . '-customfield_value")
</script>';
replace with
<script type="text/javascript">// Creates a new editor instance
tinymce.execCommand("mceAddControl",true,"field-' . $row . '-customfield_value");
tinyMCE.init({
selector: "textarea.mceInsertContentNew",
height: 500,
theme: "modern",
plugins: "print preview fullpage searchreplace autolink directionality visualblocks visualchars fullscreen image link media template codesample table charmap hr pagebreak nonbreaking anchor toc insertdatetime advlist lists textcolor wordcount imagetools contextmenu colorpicker textpattern",
toolbar1: "formatselect | bold italic strikethrough forecolor backcolor | link | alignleft aligncenter alignright alignjustify | numlist bullist outdent indent | removeformat",
image_advtab: true,
});
</script>';
Now, retry fresh page product VM you see ok