diff -r 6b3523f81f42 -r 26744ad37953 cubicweb/web/views/forms.py
--- a/cubicweb/web/views/forms.py	Fri Apr 05 17:21:14 2019 +0200
+++ b/cubicweb/web/views/forms.py	Fri Apr 05 17:58:19 2019 +0200
@@ -45,8 +45,6 @@
 import time
 import inspect
 
-from six import text_type
-
 from logilab.common import dictattr, tempattr
 from logilab.common.decorators import iclassmethod, cached
 from logilab.common.textutils import splitstrip
@@ -286,7 +284,7 @@
                 except ProcessFormError as exc:
                     errors.append((field, exc))
             if errors:
-                errors = dict((f.role_name(), text_type(ex)) for f, ex in errors)
+                errors = dict((f.role_name(), str(ex)) for f, ex in errors)
                 raise ValidationError(None, errors)
             return processed