--- a/intl/hyphenation/glue/nsHyphenationManager.cpp
+++ b/intl/hyphenation/glue/nsHyphenationManager.cpp
@@ -14,16 +14,18 @@
 #include "nsDirectoryServiceDefs.h"
 #include "nsNetUtil.h"
 #include "nsUnicharUtils.h"
 #include "mozilla/Preferences.h"
 #include "nsZipArchive.h"
 #include "mozilla/Services.h"
 #include "nsIObserverService.h"
 #include "nsCRT.h"
+#include "nsAppDirectoryServiceDefs.h"
+#include "nsDirectoryServiceUtils.h"
 
 using namespace mozilla;
 
 static const char kIntlHyphenationAliasPrefix[] = "intl.hyphenation-alias.";
 static const char kMemoryPressureNotification[] = "memory-pressure";
 
 nsHyphenationManager *nsHyphenationManager::sInstance = nullptr;
 
@@ -163,16 +165,24 @@ nsHyphenationManager::LoadPatternList()
                    NS_GET_IID(nsIFile), getter_AddRefs(appDir));
   if (NS_SUCCEEDED(rv)) {
     appDir->AppendNative(NS_LITERAL_CSTRING("hyphenation"));
     bool equals;
     if (NS_SUCCEEDED(appDir->Equals(greDir, &equals)) && !equals) {
       LoadPatternListFromDir(appDir);
     }
   }
+
+  nsCOMPtr<nsIFile> profileDir;
+  rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_LOCAL_50_DIR,
+                                       getter_AddRefs(profileDir));
+  if (NS_SUCCEEDED(rv)) {
+      profileDir->AppendNative(NS_LITERAL_CSTRING("hyphenation"));
+      LoadPatternListFromDir(profileDir);
+  }
 }
 
 void
 nsHyphenationManager::LoadPatternListFromOmnijar(Omnijar::Type aType)
 {
   nsCString base;
   nsresult rv = Omnijar::GetURIString(aType, base);
   if (NS_FAILED(rv)) {