diff --git a/toolkit/components/reputationservice/ApplicationReputation.cpp b/toolkit/components/reputationservice/ApplicationReputation.cpp
index 74161592bb56..680915f5bf53 100644
--- a/toolkit/components/reputationservice/ApplicationReputation.cpp
+++ b/toolkit/components/reputationservice/ApplicationReputation.cpp
@@ -1015,7 +1015,7 @@ PendingLookup::GetSpecHash(nsACString& aSpec, nsACString& hexEncodedHash)
   static const char* const hex = "0123456789ABCDEF";
   hexEncodedHash.SetCapacity(2 * binaryHash.Length());
   for (size_t i = 0; i < binaryHash.Length(); ++i) {
-    auto c = static_cast<const unsigned char>(binaryHash[i]);
+    auto c = static_cast<unsigned char>(binaryHash[i]);
     hexEncodedHash.Append(hex[(c >> 4) & 0x0F]);
     hexEncodedHash.Append(hex[c & 0x0F]);
   }
diff --git a/toolkit/components/url-classifier/Entries.h b/toolkit/components/url-classifier/Entries.h
index d664b57f1d27..c1da4c7beac6 100644
--- a/toolkit/components/url-classifier/Entries.h
+++ b/toolkit/components/url-classifier/Entries.h
@@ -104,7 +104,7 @@ struct SafebrowsingHash
 
     aStr.SetCapacity(2 * len);
     for (size_t i = 0; i < len; ++i) {
-      const char c = static_cast<const char>(buf[i]);
+      const char c = static_cast<char>(buf[i]);
       aStr.Append(lut[(c >> 4) & 0x0F]);
       aStr.Append(lut[c & 15]);
     }
diff --git a/toolkit/components/url-classifier/LookupCache.cpp b/toolkit/components/url-classifier/LookupCache.cpp
index 46421002a552..1ee16080bd5b 100644
--- a/toolkit/components/url-classifier/LookupCache.cpp
+++ b/toolkit/components/url-classifier/LookupCache.cpp
@@ -59,7 +59,7 @@ void CStringToHexString(const nsACString& aIn, nsACString& aOut)
 
   aOut.SetCapacity(2 * len);
   for (size_t i = 0; i < aIn.Length(); ++i) {
-    const char c = static_cast<const char>(aIn[i]);
+    const char c = static_cast<char>(aIn[i]);
     aOut.Append(lut[(c >> 4) & 0x0F]);
     aOut.Append(lut[c & 15]);
   }