diff --git a/boxes.py b/boxes.py
index ad929b5..b987fc0 100755
--- a/boxes.py
+++ b/boxes.py
@@ -41,7 +41,7 @@ class Boxes:
                 callback = callback[number]
                 if callable(callback):
                     callback()
-            except KeyError:
+            except (KeyError, IndexError):
                 pass
             except:
                 self.ctx.restore()