--- a/testing/web-platform/tests/tools/webdriver/webdriver/client.py
+++ b/testing/web-platform/tests/tools/webdriver/webdriver/client.py
@@ -272,16 +272,24 @@ class Window(object):
     @command
     def state(self):
         return self.rect["state"]
 
     @command
     def maximize(self):
         return self.session.send_session_command("POST", "window/maximize")
 
+    @command
+    def minimize(self):
+        return self.session.send_session_command("POST", "window/minimize")
+
+    @command
+    def fullscreen(self):
+        return self.session.send_session_command("POST", "window/fullscreen")
+
 
 class Find(object):
     def __init__(self, session):
         self.session = session
 
     @command
     def css(self, selector, all=True):
         return self._find_element("css selector", selector, all)