diff --git a/patches/chromium/.patches b/patches/chromium/.patches
index 04d88e0a5f45d..0a6b92d2bdae2 100644
--- a/patches/chromium/.patches
+++ b/patches/chromium/.patches
@@ -111,3 +111,4 @@ fix_setparentacessibile_crash_win.patch
 add_restrictions_to_allowed_extensions_for_file_system_access_api.patch
 ensure_that_showsavefilepicker_always_shows_the_extension_on_mac.patch
 sanitize_descriptions_for_file_types.patch
+mediacapabilities_use_threadsafe_static_wtf_string.patch
diff --git a/patches/chromium/mediacapabilities_use_threadsafe_static_wtf_string.patch b/patches/chromium/mediacapabilities_use_threadsafe_static_wtf_string.patch
new file mode 100644
index 0000000000000..0b188cb9c770b
--- /dev/null
+++ b/patches/chromium/mediacapabilities_use_threadsafe_static_wtf_string.patch
@@ -0,0 +1,168 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Chris Cunningham <chcunningham@chromium.org>
+Date: Fri, 1 Jan 2021 05:39:43 +0000
+Subject: MediaCapabilities: Use threadsafe static wtf::String
+
+This replaces DEFINE_THREAD_SAFE_STATIC_LOCAL(const String, ...).
+StringImpl ref counting (behind that macro) is not currently threadsafe.
+
+Bug: 1160534
+Change-Id: I70f4aa796aaefabbee36db4fcdf0fbf0defe4959
+Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2606399
+Commit-Queue: Chrome Cunningham <chcunningham@chromium.org>
+Reviewed-by: Jeremy Roman <jbroman@chromium.org>
+Auto-Submit: Chrome Cunningham <chcunningham@chromium.org>
+Cr-Commit-Position: refs/heads/master@{#839863}
+
+diff --git a/third_party/blink/renderer/modules/BUILD.gn b/third_party/blink/renderer/modules/BUILD.gn
+index 694ff382d40c3759e3cfe3a852f5b2829d43aed7..ec77ab05748046f4e828ed85cf944d8d25509cc9 100644
+--- a/third_party/blink/renderer/modules/BUILD.gn
++++ b/third_party/blink/renderer/modules/BUILD.gn
+@@ -21,12 +21,18 @@ config("modules_implementation") {
+   defines = [ "BLINK_MODULES_IMPLEMENTATION=1" ]
+ }
+ 
+-make_names("module_names") {
++make_names("indexed_db_names") {
+   in_files = [ "indexeddb/indexed_db_names.json5" ]
+   output_dir = blink_modules_output_dir
+   deps = []  # Don't use default deps (otherwise it will be circular).
+ }
+ 
++make_names("media_capabilities_names") {
++  in_files = [ "media_capabilities/media_capabilities_names.json5" ]
++  output_dir = blink_modules_output_dir
++  deps = []  # Don't use default deps (otherwise it will be circular).
++}
++
+ component("modules") {
+   output_name = "blink_modules"
+ 
+@@ -42,8 +48,9 @@ component("modules") {
+     "modules_initializer.h",
+   ]
+ 
+-  # Compile sources generated by module_names script.
+-  sources += get_target_outputs(":module_names")
++  # Compile sources generated by make_names script.
++  sources += get_target_outputs(":indexed_db_names")
++  sources += get_target_outputs(":media_capabilities_names")
+ 
+   sources += bindings_modules_v8_files
+ 
+@@ -173,8 +180,9 @@ component("modules") {
+   }
+ 
+   deps = [
++    ":indexed_db_names",
+     ":make_modules_generated",
+-    ":module_names",
++    ":media_capabilities_names",
+     "//jingle:webrtc_glue",
+     "//net:net",
+     "//third_party/blink/renderer/bindings/modules:generated",
+@@ -256,7 +264,8 @@ source_set("modules_testing") {
+ 
+ group("make_modules_generated") {
+   public_deps = [
+-    ":module_names",
++    ":indexed_db_names",
++    ":media_capabilities_names",
+     "//third_party/blink/renderer/bindings/modules:bindings_modules_generated",
+     "//third_party/blink/renderer/bindings/modules/v8:generated",
+     "//third_party/blink/renderer/core:core_event_interfaces",
+diff --git a/third_party/blink/renderer/modules/media_capabilities/DEPS b/third_party/blink/renderer/modules/media_capabilities/DEPS
+index 3b8d2749b4f486c4b0b207d4e20f966b5e573e07..1a5a3e9e3b6a031c4752cd92cf87426cae72f1d2 100644
+--- a/third_party/blink/renderer/modules/media_capabilities/DEPS
++++ b/third_party/blink/renderer/modules/media_capabilities/DEPS
+@@ -12,6 +12,7 @@ include_rules = [
+     "-third_party/blink/renderer/modules",
+     "+third_party/blink/renderer/modules/encryptedmedia",
+     "+third_party/blink/renderer/modules/media_capabilities",
++    "+third_party/blink/renderer/modules/media_capabilities_names.h",
+     "+third_party/blink/renderer/modules/mediarecorder/media_recorder_handler.h",
+     "+third_party/blink/renderer/modules/modules_export.h",
+ ]
+diff --git a/third_party/blink/renderer/modules/media_capabilities/media_capabilities.cc b/third_party/blink/renderer/modules/media_capabilities/media_capabilities.cc
+index 9b833e9c6368a3390d17c01f32edffe6f7d65895..ccb4bd082149ec7232cba64a02bfe139a047863c 100644
+--- a/third_party/blink/renderer/modules/media_capabilities/media_capabilities.cc
++++ b/third_party/blink/renderer/modules/media_capabilities/media_capabilities.cc
+@@ -54,6 +54,7 @@
+ #include "third_party/blink/renderer/modules/encryptedmedia/media_key_system_access_initializer_base.h"
+ #include "third_party/blink/renderer/modules/encryptedmedia/media_keys_controller.h"
+ #include "third_party/blink/renderer/modules/media_capabilities/media_capabilities_identifiability_metrics.h"
++#include "third_party/blink/renderer/modules/media_capabilities_names.h"
+ #include "third_party/blink/renderer/modules/mediarecorder/media_recorder_handler.h"
+ #include "third_party/blink/renderer/platform/bindings/exception_state.h"
+ #include "third_party/blink/renderer/platform/bindings/script_state.h"
+@@ -309,9 +310,9 @@ WebAudioConfiguration ToWebAudioConfiguration(
+   DCHECK(parsed_content_type.IsValid());
+   DCHECK(!parsed_content_type.GetParameters().HasDuplicatedNames());
+ 
+-  DEFINE_THREAD_SAFE_STATIC_LOCAL(const String, codecs, ("codecs"));
+   web_configuration.mime_type = parsed_content_type.MimeType().LowerASCII();
+-  web_configuration.codec = parsed_content_type.ParameterValueForName(codecs);
++  web_configuration.codec = parsed_content_type.ParameterValueForName(
++      media_capabilities_names::kCodecs);
+ 
+   // |channels| is optional and will be set to a null WebString if not present.
+   web_configuration.channels = configuration->hasChannels()
+@@ -337,9 +338,9 @@ WebVideoConfiguration ToWebVideoConfiguration(
+   DCHECK(parsed_content_type.IsValid());
+   DCHECK(!parsed_content_type.GetParameters().HasDuplicatedNames());
+ 
+-  DEFINE_THREAD_SAFE_STATIC_LOCAL(const String, codecs, ("codecs"));
+   web_configuration.mime_type = parsed_content_type.MimeType().LowerASCII();
+-  web_configuration.codec = parsed_content_type.ParameterValueForName(codecs);
++  web_configuration.codec = parsed_content_type.ParameterValueForName(
++      media_capabilities_names::kCodecs);
+ 
+   DCHECK(configuration->hasWidth());
+   web_configuration.width = configuration->width();
+@@ -599,9 +600,9 @@ bool ParseContentType(const String& content_type,
+     return false;
+   }
+ 
+-  DEFINE_THREAD_SAFE_STATIC_LOCAL(const String, codecs, ("codecs"));
+   *mime_type = parsed_content_type.MimeType().LowerASCII();
+-  *codec = parsed_content_type.ParameterValueForName(codecs);
++  *codec = parsed_content_type.ParameterValueForName(
++      media_capabilities_names::kCodecs);
+   return true;
+ }
+ 
+diff --git a/third_party/blink/renderer/modules/media_capabilities/media_capabilities_names.json5 b/third_party/blink/renderer/modules/media_capabilities/media_capabilities_names.json5
+new file mode 100644
+index 0000000000000000000000000000000000000000..01f9a0f705da3fad7708cccbd22c9a8c1789ff0c
+--- /dev/null
++++ b/third_party/blink/renderer/modules/media_capabilities/media_capabilities_names.json5
+@@ -0,0 +1,9 @@
++{
++  metadata: {
++    namespace: "media_capabilities_names",
++  },
++
++  data: [
++    "codecs",
++  ],
++}
+diff --git a/third_party/blink/renderer/modules/modules_initializer.cc b/third_party/blink/renderer/modules/modules_initializer.cc
+index e1cfdcbddb11a752d392bb97b1e25e56e8416a77..1b15f6e760c85125dbc05af37ed6eee683718d9a 100644
+--- a/third_party/blink/renderer/modules/modules_initializer.cc
++++ b/third_party/blink/renderer/modules/modules_initializer.cc
+@@ -63,6 +63,7 @@
+ #include "third_party/blink/renderer/modules/launch/web_launch_service_impl.h"
+ #include "third_party/blink/renderer/modules/manifest/manifest_manager.h"
+ #include "third_party/blink/renderer/modules/media/audio/audio_renderer_sink_cache.h"
++#include "third_party/blink/renderer/modules/media_capabilities_names.h"
+ #include "third_party/blink/renderer/modules/media_controls/media_controls_impl.h"
+ #include "third_party/blink/renderer/modules/mediasource/media_source_registry_impl.h"
+ #include "third_party/blink/renderer/modules/mediastream/user_media_client.h"
+@@ -119,6 +120,7 @@ void ModulesInitializer::Initialize() {
+   Document::RegisterEventFactory(EventModulesFactory::Create());
+   ModuleBindingsInitializer::Init();
+   indexed_db_names::Init();
++  media_capabilities_names::Init();
+   AXObjectCache::Init(AXObjectCacheImpl::Create);
+   DraggedIsolatedFileSystem::Init(
+       DraggedIsolatedFileSystemImpl::PrepareForDataObject);