diff --git a/weboob/browser/filters/standard.py b/weboob/browser/filters/standard.py
index 8f1eeb5d04d4c82c504af5e569694fb49a8887bf..4c052954e40e2393d817a8864f9a69d5d9b087b0 100644
--- a/weboob/browser/filters/standard.py
+++ b/weboob/browser/filters/standard.py
@@ -119,6 +119,9 @@ class Base(Filter):
 
     def __call__(self, item):
         base = self.select(self.base, item)
+        if isinstance(base, list):
+            assert len(base) == 1, 'If using a list, there must be one element only'
+            base = base[0]
         return self.select(self.selector, base)
 
     def __init__(self, base, selector=None, default=_NO_DEFAULT):