diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservo.py b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservo.py
index 01e201e2abe..485cdc5c98d 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservo.py
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservo.py
@@ -33,7 +33,6 @@ def write_hosts_file(config):
 
 
 class ServoTestharnessExecutor(ProcessTestExecutor):
-    supports_testdriver = True
     convert_result = testharness_result_converter
 
     def __init__(self, browser, server_config, timeout_multiplier=1, debug_info=None,
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservodriver.py b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservodriver.py
index d015e77b8c7..f5418192265 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservodriver.py
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/executorservodriver.py
@@ -177,6 +177,7 @@ def timeout_func(timeout):
 
 
 class ServoWebDriverTestharnessExecutor(TestharnessExecutor):
+    supports_testdriver = True
     def __init__(self, browser, server_config, timeout_multiplier=1,
                  close_after_done=True, capabilities=None, debug_info=None,
                  **kwargs):