diff --git a/dom/indexedDB/KeyPath.cpp b/dom/indexedDB/KeyPath.cpp
index 25e440d9b295..307f1b00ae81 100644
--- a/dom/indexedDB/KeyPath.cpp
+++ b/dom/indexedDB/KeyPath.cpp
@@ -258,7 +258,7 @@ nsresult GetJSValFromKeyPathString(
 // static
 Result<KeyPath, nsresult> KeyPath::Parse(const nsAString& aString) {
   KeyPath keyPath(0);
-  keyPath.SetType(STRING);
+  keyPath.SetType(KeyPathType::String);
 
   if (!keyPath.AppendStringWithValidation(aString)) {
     return Err(NS_ERROR_FAILURE);
@@ -270,7 +270,7 @@ Result<KeyPath, nsresult> KeyPath::Parse(const nsAString& aString) {
 // static
 Result<KeyPath, nsresult> KeyPath::Parse(const Sequence<nsString>& aStrings) {
   KeyPath keyPath(0);
-  keyPath.SetType(ARRAY);
+  keyPath.SetType(KeyPathType::Array);
 
   for (uint32_t i = 0; i < aStrings.Length(); ++i) {
     if (!keyPath.AppendStringWithValidation(aStrings[i])) {
@@ -453,7 +453,7 @@ KeyPath KeyPath::DeserializeFromString(const nsAString& aString) {
   KeyPath keyPath(0);
 
   if (!aString.IsEmpty() && aString.First() == ',') {
-    keyPath.SetType(ARRAY);
+    keyPath.SetType(KeyPathType::Array);
 
     // We use a comma in the beginning to indicate that it's an array of
     // key paths. This is to be able to tell a string-keypath from an
@@ -475,7 +475,7 @@ KeyPath KeyPath::DeserializeFromString(const nsAString& aString) {
     return keyPath;
   }
 
-  keyPath.SetType(STRING);
+  keyPath.SetType(KeyPathType::String);
   keyPath.mStrings.AppendElement(aString);
 
   return keyPath;
diff --git a/dom/indexedDB/KeyPath.h b/dom/indexedDB/KeyPath.h
index 109d909e25e8..75cfaf8d34b9 100644
--- a/dom/indexedDB/KeyPath.h
+++ b/dom/indexedDB/KeyPath.h
@@ -41,16 +41,18 @@ class KeyPath {
   friend class IndexMetadata;
   friend class ObjectStoreMetadata;
 
-  KeyPath() : mType(NONEXISTENT) { MOZ_COUNT_CTOR(KeyPath); }
+  KeyPath() : mType(KeyPathType::NonExistent) { MOZ_COUNT_CTOR(KeyPath); }
 
  public:
-  enum KeyPathType { NONEXISTENT, STRING, ARRAY, ENDGUARD };
+  enum class KeyPathType { NonExistent, String, Array, EndGuard };
 
   void SetType(KeyPathType aType);
 
   bool AppendStringWithValidation(const nsAString& aString);
 
-  explicit KeyPath(int aDummy) : mType(NONEXISTENT) { MOZ_COUNT_CTOR(KeyPath); }
+  explicit KeyPath(int aDummy) : mType(KeyPathType::NonExistent) {
+    MOZ_COUNT_CTOR(KeyPath);
+  }
 
   KeyPath(KeyPath&& aOther) {
     MOZ_COUNT_CTOR(KeyPath);
@@ -85,14 +87,14 @@ class KeyPath {
                               Key& aKey, ExtractOrCreateKeyCallback aCallback,
                               void* aClosure) const;
 
-  inline bool IsValid() const { return mType != NONEXISTENT; }
+  inline bool IsValid() const { return mType != KeyPathType::NonExistent; }
 
-  inline bool IsArray() const { return mType == ARRAY; }
+  inline bool IsArray() const { return mType == KeyPathType::Array; }
 
-  inline bool IsString() const { return mType == STRING; }
+  inline bool IsString() const { return mType == KeyPathType::String; }
 
   inline bool IsEmpty() const {
-    return mType == STRING && mStrings[0].IsEmpty();
+    return mType == KeyPathType::String && mStrings[0].IsEmpty();
   }
 
   bool operator==(const KeyPath& aOther) const {
diff --git a/dom/indexedDB/SerializationHelpers.h b/dom/indexedDB/SerializationHelpers.h
index bcfe37b3807f..b0818b5cabce 100644
--- a/dom/indexedDB/SerializationHelpers.h
+++ b/dom/indexedDB/SerializationHelpers.h
@@ -46,8 +46,8 @@ template <>
 struct ParamTraits<mozilla::dom::indexedDB::KeyPath::KeyPathType>
     : public ContiguousEnumSerializer<
           mozilla::dom::indexedDB::KeyPath::KeyPathType,
-          mozilla::dom::indexedDB::KeyPath::NONEXISTENT,
-          mozilla::dom::indexedDB::KeyPath::ENDGUARD> {};
+          mozilla::dom::indexedDB::KeyPath::KeyPathType::NonExistent,
+          mozilla::dom::indexedDB::KeyPath::KeyPathType::EndGuard> {};
 
 template <>
 struct ParamTraits<mozilla::dom::indexedDB::KeyPath> {