diff --git a/base_external_system/__manifest__.py b/base_external_system/__manifest__.py
index ca837198..90081ec1 100644
--- a/base_external_system/__manifest__.py
+++ b/base_external_system/__manifest__.py
@@ -4,7 +4,7 @@
 {
     "name": "Base External System",
     "summary": "Data models allowing for connection to external systems.",
-    "version": "13.0.1.0.0",
+    "version": "15.0.1.0.0",
     "category": "Base",
     "website": "https://github.com/OCA/server-backend",
     "author": "LasLabs, " "Odoo Community Association (OCA)",
diff --git a/base_external_system/models/external_system_os.py b/base_external_system/models/external_system_os.py
index 8ff2a501..19850c6a 100644
--- a/base_external_system/models/external_system_os.py
+++ b/base_external_system/models/external_system_os.py
@@ -23,7 +23,7 @@ class ExternalSystemOs(models.Model):
         """Return a usable client representing the remote system."""
         super(ExternalSystemOs, self).external_get_client()
         if self.system_id.remote_path:
-            self.previous_dir = os.getcwd()
+            ExternalSystemOs.previous_dir = os.getcwd()
             os.chdir(self.system_id.remote_path)
         return os
 
@@ -34,7 +34,8 @@ class ExternalSystemOs(models.Model):
             client (mixed): The client that was returned by
              ``external_get_client``.
         """
-        super(ExternalSystemOs, self).external_destroy_client(client)
-        if self.previous_dir:
-            os.chdir(self.previous_dir)
-            self.previous_dir = None
+        result = super(ExternalSystemOs, self).external_destroy_client(client)
+        if ExternalSystemOs.previous_dir:
+            os.chdir(ExternalSystemOs.previous_dir)
+            ExternalSystemOs.previous_dir = None
+        return result
diff --git a/base_external_system/readme/CONTRIBUTORS.rst b/base_external_system/readme/CONTRIBUTORS.rst
index 5a590489..f484d8b9 100644
--- a/base_external_system/readme/CONTRIBUTORS.rst
+++ b/base_external_system/readme/CONTRIBUTORS.rst
@@ -1,3 +1,6 @@
 * Dave Lasley <dave@laslabs.com>
-* Alexandre Díaz <alexandre.diaz@tecnativa.com>
 * Ronald Portier <ronald@therp.nl>
+* `Tecnativa <https://www.tecnativa.com>`__:
+
+  * Alexandre Díaz
+  * César A. Sánchez
diff --git a/base_external_system/tests/test_external_system_os.py b/base_external_system/tests/test_external_system_os.py
index 6e4d55cb..130082b1 100644
--- a/base_external_system/tests/test_external_system_os.py
+++ b/base_external_system/tests/test_external_system_os.py
@@ -16,8 +16,9 @@ class TestExternalSystemOs(Common):
     @classmethod
     def tearDownClass(cls):
         """Set the working dir back to origin, just in case."""
-        super(TestExternalSystemOs, cls).tearDownClass()
+        result = super(TestExternalSystemOs, cls).tearDownClass()
         os.chdir(cls.working_dir)
+        return result
 
     def setUp(self):
         super(TestExternalSystemOs, self).setUp()
diff --git a/base_external_system/views/external_system_view.xml b/base_external_system/views/external_system_view.xml
index ada662a2..ec0ee254 100644
--- a/base_external_system/views/external_system_view.xml
+++ b/base_external_system/views/external_system_view.xml
@@ -53,7 +53,7 @@
         <field name="name">external.system.view.tree</field>
         <field name="model">external.system</field>
         <field name="arch" type="xml">
-            <tree string="External Systems">
+            <tree>
                 <field name="name" />
                 <field name="host" />
                 <field name="port" />