diff --git a/etc/taskcluster/decision_task.py b/etc/taskcluster/decision_task.py
index b67defe5c46..4178e953cda 100644
--- a/etc/taskcluster/decision_task.py
+++ b/etc/taskcluster/decision_task.py
@@ -614,7 +614,7 @@ def wpt_chunks(platform, make_chunk_task, build_task, total_chunks, processes,
         # https://github.com/servo/servo/issues/22438
         if this_chunk == 0:
             task.with_script("""
-                time python2 ./mach test-wpt --release --binary-arg=--multiprocess \
+                time python ./mach test-wpt --release --binary-arg=--multiprocess \
                     --processes $PROCESSES \
                     --log-raw test-wpt-mp.log \
                     --log-errorsummary wpt-mp-errorsummary.log \
diff --git a/etc/taskcluster/decisionlib.py b/etc/taskcluster/decisionlib.py
index ec6c6b50479..6deca94bacf 100644
--- a/etc/taskcluster/decisionlib.py
+++ b/etc/taskcluster/decisionlib.py
@@ -685,7 +685,7 @@ class MacOsGenericWorkerTask(UnixTaskMixin, GenericWorkerTask):
         # So concatenate scripts and use a single `bash` command instead.
         return [
             [
-                "/bin/bash", "--login", "-x", "-e", "-c",
+                "/bin/bash", "--login", "-x", "-e", "-o", "pipefail", "-c",
                 deindent("\n".join(self.scripts))
             ]
         ]
@@ -749,7 +749,7 @@ class DockerWorkerTask(UnixTaskMixin, Task):
             "image": self.docker_image,
             "maxRunTime": self.max_run_time_minutes * 60,
             "command": [
-                "/bin/bash", "--login", "-x", "-e", "-c",
+                "/bin/bash", "--login", "-x", "-e", "-o", "pipefail", "-c",
                 deindent("\n".join(self.scripts))
             ],
         }
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index d435fe1652e..fe3c8c39771 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -345756,7 +345756,7 @@
         []
        ],
        "executorservodriver.py": [
-        "425f40223f77535d4ea34d75790e8facce30f77a",
+        "2e47a22a9c92b4caada29db358c08104793d2770",
         []
        ],
        "executorwebdriver.py": [
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 425f40223f7..2e47a22a9c9 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
@@ -277,7 +277,7 @@ class ServoWebDriverRefTestExecutor(RefTestExecutor):
 
         return ServoWebDriverRun(self.logger,
                                  self._screenshot,
-                                 self.protocol.session,
+                                 self.protocol,
                                  self.test_url(test),
                                  timeout,
                                  self.extra_timeout).run()