bug #6185 Add extra check for empty referrer value in form theme twig…

… template (nzhiti)

This PR was merged into the 4.x branch.

Discussion
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Add extra check for empty referrer value in form theme twig template

Closes : #6184

Commits
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994c1e2 Add extra check for empty referrer value in form theme twig template

src/Resources/views/crud/form_theme.html.twig

@@ -7,8 +7,9 @@
     {% endif %}
 
     {{ parent() }}
-
-    <input type="hidden" name="referrer" value="{{ ea.request.query.get('referrer') }}">
+    {% if ea.request.query.get('referrer')  %}
+        <input type="hidden" name="referrer" value="{{ ea.request.query.get('referrer') }}">
+    {% endif %}
 {% endblock form_start %}
 
 {% block form_end %}