diff --git a/bazel/envoy_mobile_repositories.bzl b/bazel/envoy_mobile_repositories.bzl
index 7d634d6292..9956bc4327 100644
--- a/bazel/envoy_mobile_repositories.bzl
+++ b/bazel/envoy_mobile_repositories.bzl
@@ -15,6 +15,18 @@ def envoy_mobile_repositories():
     python_repos()
 
 def upstream_envoy_overrides():
+    # Workaround due to a Detekt version compatibility with protobuf: https://github.com/envoyproxy/envoy-mobile/issues/1869
+    http_archive(
+        name = "com_google_protobuf",
+        patch_args = ["-p1"],
+        patches = [
+            "@envoy_mobile//bazel:protobuf.patch",
+        ],
+        sha256 = "d7371dc2d46fddac1af8cb27c0394554b068768fc79ecaf5be1a1863e8ff3392",
+        strip_prefix = "protobuf-3.16.0",
+        urls = ["https://github.com/protocolbuffers/protobuf/releases/download/v3.16.0/protobuf-all-3.16.0.tar.gz"],
+    )
+
     # Workaround old NDK version breakages https://github.com/lyft/envoy-mobile/issues/934
     http_archive(
         name = "com_github_libevent_libevent",
diff --git a/bazel/protobuf.patch b/bazel/protobuf.patch
index e9f34fa5ec..e786c7ebe1 100644
--- a/bazel/protobuf.patch
+++ b/bazel/protobuf.patch
@@ -1,94 +1,37 @@
+# https://github.com/protocolbuffers/protobuf/pull/6720
+diff --git a/third_party/BUILD b/third_party/BUILD
+new file mode 100644
+index 0000000000..b66101a39a
+--- /dev/null
++++ b/third_party/BUILD
+@@ -0,0 +1 @@
++exports_files(["six.BUILD", "zlib.BUILD"])
+
+# patching for zlib binding
 diff --git a/BUILD b/BUILD
-index 07ee629..09541cf 100644
+index efc3d8e7f..746ad4851 100644
 --- a/BUILD
 +++ b/BUILD
-@@ -260,36 +260,38 @@ cc_library(
- # Map of all well known protos.
- # name => (include path, imports)
- WELL_KNOWN_PROTO_MAP = {
--    "any": ("src/google/protobuf/any.proto", []),
-+    "any": ("google/protobuf/any.proto", []),
-     "api": (
--        "src/google/protobuf/api.proto",
-+        "google/protobuf/api.proto",
-         [
-             "source_context",
-             "type",
-         ],
-     ),
-     "compiler_plugin": (
--        "src/google/protobuf/compiler/plugin.proto",
-+        "google/protobuf/compiler/plugin.proto",
-         ["descriptor"],
-     ),
--    "descriptor": ("src/google/protobuf/descriptor.proto", []),
--    "duration": ("src/google/protobuf/duration.proto", []),
--    "empty": ("src/google/protobuf/empty.proto", []),
--    "field_mask": ("src/google/protobuf/field_mask.proto", []),
--    "source_context": ("src/google/protobuf/source_context.proto", []),
--    "struct": ("src/google/protobuf/struct.proto", []),
--    "timestamp": ("src/google/protobuf/timestamp.proto", []),
-+    "descriptor": ("google/protobuf/descriptor.proto", []),
-+    "duration": ("google/protobuf/duration.proto", []),
-+    "empty": ("google/protobuf/empty.proto", []),
-+    "field_mask": ("google/protobuf/field_mask.proto", []),
-+    "source_context": ("google/protobuf/source_context.proto", []),
-+    "struct": ("google/protobuf/struct.proto", []),
-+    "timestamp": ("google/protobuf/timestamp.proto", []),
-     "type": (
--        "src/google/protobuf/type.proto",
-+        "google/protobuf/type.proto",
-         [
-             "any",
-             "source_context",
-         ],
-     ),
--    "wrappers": ("src/google/protobuf/wrappers.proto", []),
-+    "wrappers": ("google/protobuf/wrappers.proto", []),
- }
+@@ -24,7 +24,7 @@ config_setting(
+ # ZLIB configuration
+ ################################################################################
 
--WELL_KNOWN_PROTOS = [value[0] for value in WELL_KNOWN_PROTO_MAP.values()]
-+RELATIVE_WELL_KNOWN_PROTOS = [proto[1][0] for proto in WELL_KNOWN_PROTO_MAP.items()]
-+
-+WELL_KNOWN_PROTOS = ["src/" + s for s in RELATIVE_WELL_KNOWN_PROTOS]
+-ZLIB_DEPS = ["@zlib//:zlib"]
++ZLIB_DEPS = ["//external:zlib"]
 
- filegroup(
-     name = "well_known_protos",
-@@ -321,10 +323,17 @@ cc_library(
- # )
  ################################################################################
+ # Protobuf Runtime Library
+diff --git a/python/google/protobuf/__init__.py b/python/google/protobuf/__init__.py
+index 97ac28028..8b7585d9d 100644
+--- a/python/google/protobuf/__init__.py
++++ b/python/google/protobuf/__init__.py
+@@ -31,3 +31,9 @@
+ # Copyright 2007 Google Inc. All Rights Reserved.
 
-+internal_copied_filegroup(
-+    name = "_internal_wkt_protos",
-+    srcs = WELL_KNOWN_PROTOS,
-+    dest = "",
-+    strip_prefix = "src",
-+    visibility = ["//visibility:private"],
-+)
+ __version__ = '3.16.0'
 +
- [proto_library(
-     name = proto[0] + "_proto",
-     srcs = [proto[1][0]],
--    strip_import_prefix = "src",
-     visibility = ["//visibility:public"],
-     deps = [dep + "_proto" for dep in proto[1][1]],
- ) for proto in WELL_KNOWN_PROTO_MAP.items()]
-@@ -824,7 +833,8 @@ internal_copied_filegroup(
-
- # TODO(dzc): Remove this once py_proto_library can have labels in srcs, in
- # which case we can simply add :protos_python in srcs.
--COPIED_WELL_KNOWN_PROTOS = ["python/" + s[4:] for s in WELL_KNOWN_PROTOS]
-+
-+COPIED_WELL_KNOWN_PROTOS = ["python/" + s for s in RELATIVE_WELL_KNOWN_PROTOS]
-
- py_proto_library(
-     name = "protobuf_python",
-@@ -942,7 +952,7 @@ cc_library(
-
- proto_lang_toolchain(
-     name = "cc_toolchain",
--    blacklisted_protos = [proto + "_proto" for proto in WELL_KNOWN_PROTO_MAP.keys()],
-+    blacklisted_protos = [":_internal_wkt_protos_genrule"],
-     command_line = "--cpp_out=$(OUT)",
-     runtime = ":protobuf",
-     visibility = ["//visibility:public"],
++if __name__ != '__main__':
++  try:
++    __import__('pkg_resources').declare_namespace(__name__)
++  except ImportError:
++    __path__ = __import__('pkgutil').extend_path(__path__, __name__)
diff --git a/envoy b/envoy
index 3941b63661..5423325ccf 160000
--- a/envoy
+++ b/envoy
@@ -1 +1 @@
-Subproject commit 3941b63661c3ea8916cb9d370eaf26182765db68
+Subproject commit 5423325ccf04c7f50069cb8662e51208526bd4a9
diff --git a/library/common/engine.cc b/library/common/engine.cc
index 5e4e9a79c8..cd862f1fc6 100644
--- a/library/common/engine.cc
+++ b/library/common/engine.cc
@@ -100,7 +100,7 @@ envoy_status_t Engine::main(const std::string config, const std::string log_leve
 
     postinit_callback_handler_ = main_common->server()->lifecycleNotifier().registerCallback(
         Envoy::Server::ServerLifecycleNotifier::Stage::PostInit, [this]() -> void {
-          ASSERT(Thread::MainThread::isMainThread());
+          ASSERT(Thread::MainThread::isMainOrTestThread());
 
           network_configurator_ =
               Network::ConfiguratorFactory{server_->serverFactoryContext()}.get();
diff --git a/library/common/engine_common.h b/library/common/engine_common.h
index 3fce9a91ea..c979737c7a 100644
--- a/library/common/engine_common.h
+++ b/library/common/engine_common.h
@@ -39,6 +39,7 @@ class EngineCommon {
   Envoy::TerminateHandler log_on_terminate_;
 #endif
 
+  Thread::MainThread register_main_thread_;
   Envoy::OptionsImpl options_;
   Event::RealTimeSystem real_time_system_; // NO_CHECK_FORMAT(real_time)
   DefaultListenerHooks default_listener_hooks_;