--- a/testing/web-platform/tests/tools/webdriver/webdriver/client.py
+++ b/testing/web-platform/tests/tools/webdriver/webdriver/client.py
@@ -258,17 +258,16 @@ class Window(object):
 
     @position.setter
     @command
     def position(self, data):
         data = x, y
         body = {"x": x, "y": y}
         self.session.send_session_command("POST", "window/rect", body)
 
-    @property
     @command
     def maximize(self):
         return self.session.send_session_command("POST", "window/maximize")
 
 
 class Find(object):
     def __init__(self, session):
         self.session = session