diff --git a/toolkit/components/find/nsFind.cpp b/toolkit/components/find/nsFind.cpp
index 101338310c7a..b7f977747097 100644
--- a/toolkit/components/find/nsFind.cpp
+++ b/toolkit/components/find/nsFind.cpp
@@ -32,7 +32,7 @@
 using namespace mozilla;
 
 // Yikes!  Casting a char to unichar can fill with ones!
-#define CHAR_TO_UNICHAR(c) ((char16_t)(const unsigned char)c)
+#define CHAR_TO_UNICHAR(c) ((char16_t)(unsigned char)c)
 
 static NS_DEFINE_CID(kCContentIteratorCID, NS_CONTENTITERATOR_CID);
 static NS_DEFINE_CID(kCPreContentIteratorCID, NS_PRECONTENTITERATOR_CID);