--- a/testing/web-platform/meta/webdriver/tests/new_session/response.py.ini
+++ b/testing/web-platform/meta/webdriver/tests/new_session/response.py.ini
@@ -1,7 +1,6 @@
 [response.py]
-  [test_capabilites]
+  [test_capability_type\[proxy-dict\]]
     expected: FAIL
 
-  [test_data]
+  [test_capability_default_value\[proxy-default_value2\]]
     expected: FAIL
-

--- a/testing/web-platform/tests/webdriver/tests/new_session/response.py
+++ b/testing/web-platform/tests/webdriver/tests/new_session/response.py
@@ -1,53 +1,43 @@
-# META: timeout=long
+import uuid
 
-import uuid
+import pytest
 
 from tests.support.asserts import assert_success
 
 
 def test_sessionid(new_session, add_browser_capabilities):
     response, _ = new_session({"capabilities": {"alwaysMatch": add_browser_capabilities({})}})
     value = assert_success(response)
     assert isinstance(value["sessionId"], basestring)
     uuid.UUID(hex=value["sessionId"])
 
 
-def test_capabilites(new_session, add_browser_capabilities):
-    response, _ = new_session({"capabilities": {"alwaysMatch": add_browser_capabilities({})}})
-    value = assert_success(response)
-    assert isinstance(value["capabilities"], dict)
-
-    all_capabilities = set(value["capabilities"].keys())
-    expected_capabilities = {
-        "browserName",
-        "browserVersion",
-        "platformName",
-        "acceptInsecureCerts",
-        "setWindowRect",
-        "timeouts",
-        "proxy",
-        "pageLoadStrategy",
-    }
-
-    assert expected_capabilities.issubset(all_capabilities), (
-        "{0} cannot be found in {1}".format(
-            list(expected_capabilities - all_capabilities), all_capabilities))
+@pytest.mark.parametrize("capability, type", [
+    ("browserName", basestring),
+    ("browserVersion", basestring),
+    ("platformName", basestring),
+    ("acceptInsecureCerts", bool),
+    ("pageLoadStrategy", basestring),
+    ("proxy", dict),
+    ("setWindowRect", bool),
+    ("timeouts", dict),
+    ("unhandledPromptBehavior", basestring),
+])
+def test_capability_type(session, capability, type):
+    assert isinstance(session.capabilities, dict)
+    assert capability in session.capabilities
+    assert isinstance(session.capabilities[capability], type)
 
 
-def test_data(new_session, add_browser_capabilities, platform_name):
-    response, _ = new_session({"capabilities": {"alwaysMatch": add_browser_capabilities({})}})
-    value = assert_success(response)
-
-    assert isinstance(value["capabilities"]["browserName"], basestring)
-    assert isinstance(value["capabilities"]["browserVersion"], basestring)
-    if platform_name:
-        assert value["capabilities"]["platformName"] == platform_name
-    else:
-        assert "platformName" in value["capabilities"]
-    assert value["capabilities"]["acceptInsecureCerts"] is False
-    assert isinstance(value["capabilities"]["setWindowRect"], bool)
-    assert value["capabilities"]["timeouts"]["implicit"] == 0
-    assert value["capabilities"]["timeouts"]["pageLoad"] == 300000
-    assert value["capabilities"]["timeouts"]["script"] == 30000
-    assert value["capabilities"]["proxy"] == {}
-    assert value["capabilities"]["pageLoadStrategy"] == "normal"
+@pytest.mark.parametrize("capability, default_value", [
+    ("acceptInsecureCerts", False),
+    ("pageLoadStrategy", "normal"),
+    ("proxy", {}),
+    ("setWindowRect", True),
+    ("timeouts", {"implicit": 0, "pageLoad": 300000, "script": 30000}),
+    ("unhandledPromptBehavior", "dismiss and notify"),
+])
+def test_capability_default_value(session, capability, default_value):
+    assert isinstance(session.capabilities, dict)
+    assert capability in session.capabilities
+    assert session.capabilities[capability] == default_value