fix: Improved handling of optional smart link field (#210)

Author: fsbraun

djangocms_frontend/contrib/link/forms.py

@@ -114,7 +114,10 @@ def build_attrs(self, base_attrs, extra_attrs=None):
         return attrs
 
     def optgroups(self, name, value, attr=None):
-        return super(forms.Select, self).optgroups(name, value)
+        groups = super(forms.Select, self).optgroups(name, value)
+        if not self.is_required:
+            groups[0][1].insert(0, self.create_option(name, "", "", False, 0))
+        return groups
 
 
 class SmartLinkField(forms.ChoiceField):