--- a/tools/profiler/core/ProfileBufferEntry.h
+++ b/tools/profiler/core/ProfileBufferEntry.h
@@ -165,18 +165,16 @@ public:
     bool operator==(const JITAddress& aRhs) const
     {
       return mAddress == aRhs.mAddress && mStreamingGen == aRhs.mStreamingGen;
     }
     bool operator!=(const JITAddress& aRhs) const { return !(*this == aRhs); }
   };
 
   struct FrameKey {
-    // This cannot be a std::string, as it is not memmove compatible, which
-    // is used by nsHashTable
     const nsCString mLocation;
     const mozilla::Maybe<unsigned> mLine;
     const mozilla::Maybe<unsigned> mCategory;
     const mozilla::Maybe<JITAddress> mJITAddress;
     const mozilla::Maybe<uint32_t> mJITDepth;
 
     explicit FrameKey(const char* aLocation)
      : mLocation(aLocation)