diff --git a/shell/browser/browser_win.cc b/shell/browser/browser_win.cc
index f8da302748..9adf9052cd 100644
--- a/shell/browser/browser_win.cc
+++ b/shell/browser/browser_win.cc
@@ -748,7 +748,7 @@ void Browser::ShowAboutPanel() {
       "applicationName", "applicationVersion", "copyright", "credits"};
 
   const std::string* str;
-  for (std::string opt : stringOptions) {
+  for (const std::string& opt : stringOptions) {
     if ((str = dict.FindString(opt))) {
       aboutMessage.append(*str).append("\r\n");
     }
diff --git a/shell/browser/ui/webui/accessibility_ui.cc b/shell/browser/ui/webui/accessibility_ui.cc
index 0229ed3439..b85b2181a7 100644
--- a/shell/browser/ui/webui/accessibility_ui.cc
+++ b/shell/browser/ui/webui/accessibility_ui.cc
@@ -310,7 +310,7 @@ std::string RecursiveDumpAXPlatformNodeAsString(
   std::string line = node->GetDelegate()->GetData().ToString();
   std::vector<std::string> attributes = base::SplitString(
       line, " ", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
-  for (std::string attribute : attributes) {
+  for (const std::string& attribute : attributes) {
     if (ui::AXTreeFormatter::MatchesPropertyFilters(property_filters, attribute,
                                                     false)) {
       str += attribute + " ";