--- a/cubicweb/sobjects/notification.py	Fri Apr 05 17:21:14 2019 +0200
+++ b/cubicweb/sobjects/notification.py	Fri Apr 05 17:58:19 2019 +0200
@@ -22,8 +22,6 @@
 
 from itertools import repeat
 
-from six import text_type
-
 from logilab.common.textutils import normalize_text
 from logilab.common.registry import yes
 
@@ -179,7 +177,7 @@
     def context(self, **kwargs):
         entity = self.cw_rset.get_entity(self.cw_row or 0, self.cw_col or 0)
         for key, val in kwargs.items():
-            if val and isinstance(val, text_type) and val.strip():
+            if val and isinstance(val, str) and val.strip():
                 kwargs[key] = self._cw._(val)
         kwargs.update({'user': self.user_data['login'],
                        'eid': entity.eid,
@@ -252,7 +250,7 @@
 
 
 def format_value(value):
-    if isinstance(value, text_type):
+    if isinstance(value, str):
         return u'"%s"' % value
     return value