diff --git a/conftest.py b/conftest.py
index 5ae7aacb8e9e52e8f7672d1b6b77a2c0ff91c546..c989bd81b7443900b7e4d2953b5be6ea73763b91 100644
--- a/conftest.py
+++ b/conftest.py
@@ -111,14 +111,20 @@ class IPyNbTest(pytest.Item):
 
         # in notebooks there is an implicit plt.show() - if this is not called a warning is shown when the next
         # plot is created. This warning is suppressed here
+        # Also animations cannot be shown, which also leads to a warning.
         exec("import warnings;"
-             "warnings.filterwarnings('ignore', 'Adding an axes using the same arguments as a previous.*');",
+             "warnings.filterwarnings('ignore', 'Adding an axes using the same arguments as a previous.*');"
+             "warnings.filterwarnings('ignore', 'Animation was deleted without rendering anything.*');",
              global_dict)
         with tempfile.NamedTemporaryFile() as f:
             f.write(self.code.encode())
             f.flush()
             runpy.run_path(f.name, init_globals=global_dict, run_name=self.name)
 
+        #   Close any open figures
+        exec("import matplotlib.pyplot as p; "
+             "p.close('all')", global_dict)
+
 
 class IPyNbFile(pytest.File):
     def collect(self):