diff --git a/chrome/browser/ui/webui/internals/web_app/web_app_internals_page_handler_impl.cc b/chrome/browser/ui/webui/internals/web_app/web_app_internals_page_handler_impl.cc
index 339fc5a6c..5e23be6fb 100644
--- a/chrome/browser/ui/webui/internals/web_app/web_app_internals_page_handler_impl.cc
+++ b/chrome/browser/ui/webui/internals/web_app/web_app_internals_page_handler_impl.cc
@@ -23,7 +23,7 @@ namespace {
 
 template <typename T>
 std::string ConvertToString(const T& value) {
-  return (std::stringstream() << value).str();
+  return static_cast<const std::stringstream &>(std::stringstream() << value).str();
 }
 
 }  // namespace
diff --git a/chrome/browser/web_applications/external_web_app_manager.cc b/chrome/browser/web_applications/external_web_app_manager.cc
index 3da14c154..64c2e80a9 100644
--- a/chrome/browser/web_applications/external_web_app_manager.cc
+++ b/chrome/browser/web_applications/external_web_app_manager.cc
@@ -100,7 +100,7 @@ LoadedConfigs LoadConfigsBlocking(const base::FilePath& config_dir) {
         deserializer.Deserialize(nullptr, &error_msg);
     if (!app_config) {
       result.errors.push_back(
-          (std::stringstream() << file << " was not valid JSON: " << error_msg)
+          static_cast<const std::stringstream &>(std::stringstream() << file << " was not valid JSON: " << error_msg)
               .str());
       VLOG(1) << result.errors.back();
       continue;
diff --git a/chrome/browser/web_applications/external_web_app_utils.cc b/chrome/browser/web_applications/external_web_app_utils.cc
index 8b3414d06..6d0718198 100644
--- a/chrome/browser/web_applications/external_web_app_utils.cc
+++ b/chrome/browser/web_applications/external_web_app_utils.cc
@@ -158,7 +158,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   options.require_manifest = true;
 
   if (app_config.type() != base::Value::Type::DICTIONARY) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " was not a dictionary as the top level")
         .str();
   }
@@ -166,18 +166,18 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   // user_type
   const base::Value* value = app_config.FindListKey(kUserType);
   if (!value) {
-    return (std::stringstream() << file << " missing " << kUserType).str();
+    return static_cast<const std::stringstream &>(std::stringstream() << file << " missing " << kUserType).str();
   }
   for (const auto& item : value->GetList()) {
     if (!item.is_string()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " has invalid " << kUserType << item)
           .str();
     }
     options.user_type_allowlist.push_back(item.GetString());
   }
   if (options.user_type_allowlist.empty()) {
-    return (std::stringstream() << file << " has empty " << kUserType).str();
+    return static_cast<const std::stringstream &>(std::stringstream() << file << " has empty " << kUserType).str();
   }
 
   // feature_name
@@ -188,18 +188,18 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   // app_url
   value = app_config.FindKeyOfType(kAppUrl, base::Value::Type::STRING);
   if (!value) {
-    return (std::stringstream() << file << " had a missing " << kAppUrl).str();
+    return static_cast<const std::stringstream &>(std::stringstream() << file << " had a missing " << kAppUrl).str();
   }
   options.install_url = GURL(value->GetString());
   if (!options.install_url.is_valid()) {
-    return (std::stringstream() << file << " had an invalid " << kAppUrl).str();
+    return static_cast<const std::stringstream &>(std::stringstream() << file << " had an invalid " << kAppUrl).str();
   }
 
   // only_for_new_users
   value = app_config.FindKey(kOnlyForNewUsers);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kOnlyForNewUsers)
           .str();
     }
@@ -211,7 +211,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kHideFromUser);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kHideFromUser)
           .str();
     }
@@ -226,7 +226,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kCreateShortcuts);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kCreateShortcuts)
           .str();
     }
@@ -242,7 +242,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kDisableIfArcSupported);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kDisableIfArcSupported)
           .str();
     }
@@ -253,7 +253,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kDisableIfTabletFormFactor);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kDisableIfTabletFormFactor)
           .str();
     }
@@ -263,7 +263,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   // launch_container
   value = app_config.FindKeyOfType(kLaunchContainer, base::Value::Type::STRING);
   if (!value) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " had an invalid " << kLaunchContainer)
         .str();
   }
@@ -273,7 +273,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   } else if (launch_container_str == kLaunchContainerWindow) {
     options.user_display_mode = DisplayMode::kStandalone;
   } else {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " had an invalid " << kLaunchContainer << ": "
             << launch_container_str)
         .str();
@@ -283,7 +283,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kLaunchQueryParams);
   if (value) {
     if (!value->is_string()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kLaunchQueryParams)
           .str();
     }
@@ -294,7 +294,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kLoadAndAwaitServiceWorkerRegistration);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream() << file << " had an invalid "
+      return static_cast<const std::stringstream &>(std::stringstream() << file << " had an invalid "
                                   << kLoadAndAwaitServiceWorkerRegistration)
           .str();
     }
@@ -305,20 +305,20 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kServiceWorkerRegistrationUrl);
   if (value) {
     if (!options.load_and_await_service_worker_registration) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " should not specify a "
               << kServiceWorkerRegistrationUrl << " while "
               << kLoadAndAwaitServiceWorkerRegistration << " is disabled")
           .str();
     }
     if (!value->is_string()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kServiceWorkerRegistrationUrl)
           .str();
     }
     options.service_worker_registration_url.emplace(value->GetString());
     if (!options.service_worker_registration_url->is_valid()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kServiceWorkerRegistrationUrl)
           .str();
     }
@@ -328,7 +328,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kUninstallAndReplace);
   if (value) {
     if (!value->is_list()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kUninstallAndReplace)
           .str();
     }
@@ -336,7 +336,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
 
     for (const auto& app_id_value : uninstall_and_replace_values) {
       if (!app_id_value.is_string()) {
-        return (std::stringstream() << file << " had an invalid "
+        return static_cast<const std::stringstream &>(std::stringstream() << file << " had an invalid "
                                     << kUninstallAndReplace << " entry")
             .str();
       }
@@ -348,7 +348,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   value = app_config.FindKey(kOnlyUseOfflineManifest);
   if (value) {
     if (!value->is_bool()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " had an invalid " << kOnlyUseOfflineManifest)
           .str();
     }
@@ -369,7 +369,7 @@ OptionsOrError ParseConfig(FileUtilsWrapper& file_utils,
   }
 
   if (options.only_use_app_info_factory && !options.app_info_factory) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << kOnlyUseOfflineManifest << " set with no "
             << kOfflineManifest << " available")
         .str();
@@ -389,7 +389,7 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   const std::string* name_string =
       offline_manifest.FindStringKey(kOfflineManifestName);
   if (!name_string) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestName
             << " missing or invalid.")
         .str();
@@ -397,7 +397,7 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   if (!base::UTF8ToUTF16(name_string->data(), name_string->size(),
                          &app_info.title) ||
       app_info.title.empty()) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestName
             << " invalid: " << *name_string)
         .str();
@@ -407,14 +407,14 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   const std::string* start_url_string =
       offline_manifest.FindStringKey(kOfflineManifestStartUrl);
   if (!start_url_string) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " "
             << kOfflineManifestStartUrl << " missing or invalid.")
         .str();
   }
   app_info.start_url = GURL(*start_url_string);
   if (!app_info.start_url.is_valid()) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " "
             << kOfflineManifestStartUrl << " invalid: " << *start_url_string)
         .str();
@@ -424,21 +424,21 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   const std::string* scope_string =
       offline_manifest.FindStringKey(kOfflineManifestScope);
   if (!scope_string) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestScope
             << " missing or invalid.")
         .str();
   }
   app_info.scope = GURL(*scope_string);
   if (!app_info.scope.is_valid()) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestScope
             << " invalid: " << *scope_string)
         .str();
   }
   if (!base::StartsWith(app_info.start_url.path(), app_info.scope.path(),
                         base::CompareCase::SENSITIVE)) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestScope
             << " (" << app_info.start_url << ") not within "
             << kOfflineManifestScope << " (" << app_info.scope << ").")
@@ -449,14 +449,14 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   const std::string* display_string =
       offline_manifest.FindStringKey(kOfflineManifestDisplay);
   if (!display_string) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestDisplay
             << " missing or invalid.")
         .str();
   }
   DisplayMode display = blink::DisplayModeFromString(*display_string);
   if (display == DisplayMode::kUndefined) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " " << kOfflineManifestDisplay
             << " invalid: " << display_string)
         .str();
@@ -467,14 +467,14 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
   const base::Value* icon_files =
       offline_manifest.FindListKey(kOfflineManifestIconAnyPngs);
   if (!icon_files || icon_files->GetList().empty()) {
-    return (std::stringstream()
+    return static_cast<const std::stringstream &>(std::stringstream()
             << file << " " << kOfflineManifest << " "
             << kOfflineManifestIconAnyPngs << " missing, empty or invalid.")
         .str();
   }
   for (const base::Value& icon_file : icon_files->GetList()) {
     if (!icon_file.is_string()) {
-      return (std::stringstream()
+      return static_cast<const std::stringstream &>(std::stringstream()
               << file << " " << kOfflineManifest << " "
               << kOfflineManifestIconAnyPngs << " " << icon_file << " invalid.")
           .str();
@@ -483,7 +483,7 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
     base::FilePath icon_path = dir.AppendASCII(icon_file.GetString());
     std::string icon_data;
     if (!file_utils.ReadFileToString(icon_path, &icon_data)) {
-      return (std::stringstream() << file << " " << kOfflineManifest << " "
+      return static_cast<const std::stringstream &>(std::stringstream() << file << " " << kOfflineManifest << " "
                                   << kOfflineManifestIconAnyPngs << " "
                                   << icon_file << " failed to read.")
           .str();
@@ -493,14 +493,14 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
     if (!gfx::PNGCodec::Decode(
             reinterpret_cast<const unsigned char*>(icon_data.c_str()),
             icon_data.size(), &bitmap)) {
-      return (std::stringstream() << file << " " << kOfflineManifest << " "
+      return static_cast<const std::stringstream &>(std::stringstream() << file << " " << kOfflineManifest << " "
                                   << kOfflineManifestIconAnyPngs << " "
                                   << icon_file << " failed to decode.")
           .str();
     }
 
     if (bitmap.width() != bitmap.height()) {
-      return (std::stringstream() << file << " " << kOfflineManifest << " "
+      return static_cast<const std::stringstream &>(std::stringstream() << file << " " << kOfflineManifest << " "
                                   << kOfflineManifestIconAnyPngs << " "
                                   << icon_file << " must be square: "
                                   << bitmap.width() << "x" << bitmap.height())
@@ -521,7 +521,7 @@ WebApplicationInfoFactoryOrError ParseOfflineManifest(
     SkColor theme_color;
     if (!theme_color_argb_hex ||
         !base::HexStringToUInt(*theme_color_argb_hex, &theme_color)) {
-      return (std::stringstream() << file << " " << kOfflineManifest << " "
+      return static_cast<const std::stringstream &>(std::stringstream() << file << " " << kOfflineManifest << " "
                                   << kOfflineManifestThemeColorArgbHex
                                   << " invalid: " << *theme_color_value)
           .str();