diff --git a/src/catch2/matchers/catch_matchers_string.cpp b/src/catch2/matchers/catch_matchers_string.cpp
index 25afa967..90815c67 100644
--- a/src/catch2/matchers/catch_matchers_string.cpp
+++ b/src/catch2/matchers/catch_matchers_string.cpp
@@ -21,10 +21,10 @@ namespace Matchers {
                ? toLower( str )
                : str;
     }
-    std::string CasedString::caseSensitivitySuffix() const {
-        return m_caseSensitivity == CaseSensitive::No
-               ? " (case insensitive)"
-               : std::string();
+    StringRef CasedString::caseSensitivitySuffix() const {
+        return m_caseSensitivity == CaseSensitive::Yes
+                   ? StringRef()
+                   : " (case insensitive)"_sr;
     }
 
 
diff --git a/src/catch2/matchers/catch_matchers_string.hpp b/src/catch2/matchers/catch_matchers_string.hpp
index abbf57b7..fc074842 100644
--- a/src/catch2/matchers/catch_matchers_string.hpp
+++ b/src/catch2/matchers/catch_matchers_string.hpp
@@ -10,6 +10,7 @@
 
 #include <catch2/matchers/catch_matchers.hpp>
 #include <catch2/internal/catch_case_sensitive.hpp>
+#include <catch2/internal/catch_stringref.hpp>
 
 #include <string>
 
@@ -19,7 +20,7 @@ namespace Matchers {
     struct CasedString {
         CasedString( std::string const& str, CaseSensitive caseSensitivity );
         std::string adjustString( std::string const& str ) const;
-        std::string caseSensitivitySuffix() const;
+        StringRef caseSensitivitySuffix() const;
 
         CaseSensitive m_caseSensitivity;
         std::string m_str;