diff --git a/AK/FlyString.cpp b/AK/FlyString.cpp
index 468f97519c..fefdc76ead 100644
--- a/AK/FlyString.cpp
+++ b/AK/FlyString.cpp
@@ -17,6 +17,7 @@ namespace AK {
 struct FlyStringTableHashTraits : public Traits<Detail::StringData const*> {
     static u32 hash(Detail::StringData const* string) { return string->hash(); }
     static bool equals(Detail::StringData const* a, Detail::StringData const* b) { return *a == *b; }
+    static constexpr bool may_have_slow_equality_check() { return true; }
 };
 
 static auto& all_fly_strings()
diff --git a/AK/Utf16FlyString.cpp b/AK/Utf16FlyString.cpp
index 921ec447bf..921769558a 100644
--- a/AK/Utf16FlyString.cpp
+++ b/AK/Utf16FlyString.cpp
@@ -13,6 +13,7 @@ namespace AK {
 struct Utf16FlyStringTableHashTraits : public Traits<Detail::Utf16StringData const*> {
     static u32 hash(Detail::Utf16StringData const* string) { return string->hash(); }
     static bool equals(Detail::Utf16StringData const* a, Detail::Utf16StringData const* b) { return *a == *b; }
+    static constexpr bool may_have_slow_equality_check() { return true; }
 };
 
 static auto& all_utf16_fly_strings()