diff --git a/accessible/atk/nsMaiInterfaceText.cpp b/accessible/atk/nsMaiInterfaceText.cpp
index be8ac2b26180..d8c162855343 100644
--- a/accessible/atk/nsMaiInterfaceText.cpp
+++ b/accessible/atk/nsMaiInterfaceText.cpp
@@ -129,7 +129,7 @@ ConvertTexttoAsterisks(AccessibleWrap* accWrap, nsAString& aString)
   // convert each char to "*" when it's "password text"
   if (accWrap->NativeRole() == roles::PASSWORD_TEXT) {
     for (uint32_t i = 0; i < aString.Length(); i++)
-      aString.Replace(i, 1, NS_LITERAL_STRING("*"));
+      aString.ReplaceLiteral(i, 1, u"*");
   }
 }
 
diff --git a/dom/base/nsGlobalWindow.cpp b/dom/base/nsGlobalWindow.cpp
index 47da75e1a596..cd11cab526e5 100644
--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -11954,7 +11954,7 @@ nsGlobalWindow::ShowSlowScriptDialog(const nsString& aAddonId)
       }
 
       // Insert U+2026 HORIZONTAL ELLIPSIS
-      filenameUTF16.Replace(cutStart, cutLength, NS_LITERAL_STRING(u"\x2026"));
+      filenameUTF16.ReplaceLiteral(cutStart, cutLength, u"\x2026");
     }
     const char16_t *formatParams[] = { filenameUTF16.get() };
     rv = nsContentUtils::FormatLocalizedString(nsContentUtils::eDOM_PROPERTIES,
diff --git a/dom/html/HTMLInputElement.cpp b/dom/html/HTMLInputElement.cpp
index c2e58ed0124b..80b11500f8c1 100644
--- a/dom/html/HTMLInputElement.cpp
+++ b/dom/html/HTMLInputElement.cpp
@@ -5422,7 +5422,7 @@ HTMLInputElement::NormalizeDateTimeLocal(nsAString& aValue) const
   // Use 'T' as the separator between date string and time string.
   int32_t sepIndex = aValue.FindChar(' ');
   if (sepIndex != -1) {
-    aValue.Replace(sepIndex, 1, NS_LITERAL_STRING("T"));
+    aValue.ReplaceLiteral(sepIndex, 1, u"T");
   } else {
     sepIndex = aValue.FindChar('T');
   }
diff --git a/intl/locale/windows/OSPreferences_win.cpp b/intl/locale/windows/OSPreferences_win.cpp
index 147767c66eeb..2da7a300bf15 100644
--- a/intl/locale/windows/OSPreferences_win.cpp
+++ b/intl/locale/windows/OSPreferences_win.cpp
@@ -209,9 +209,9 @@ OSPreferences::ReadDateTimePattern(DateTimeFormatStyle aDateStyle,
     start = str->BeginReading(pos);
     str->EndReading(end);
     if (FindInReadable(NS_LITERAL_STRING("dddd"), pos, end)) {
-      str->Replace(pos - start, 4, NS_LITERAL_STRING("EEEE"));
+      str->ReplaceLiteral(pos - start, 4, u"EEEE");
     } else if (FindInReadable(NS_LITERAL_STRING("ddd"), pos, end)) {
-      str->Replace(pos - start, 3, NS_LITERAL_STRING("EEE"));
+      str->ReplaceLiteral(pos - start, 3, u"EEE");
     }
 
     // Also, Windows uses lowercase "g" or "gg" for era, but ICU wants uppercase "G"
diff --git a/netwerk/dns/nsIDNService.cpp b/netwerk/dns/nsIDNService.cpp
index 07fecca1b3a8..ba916e841e11 100644
--- a/netwerk/dns/nsIDNService.cpp
+++ b/netwerk/dns/nsIDNService.cpp
@@ -653,7 +653,7 @@ void nsIDNService::normalizeFullStops(nsAString& s)
       case 0x3002:
       case 0xFF0E:
       case 0xFF61:
-        s.Replace(index, 1, NS_LITERAL_STRING("."));
+        s.ReplaceLiteral(index, 1, u".");
         break;
       default:
         break;
diff --git a/toolkit/crashreporter/nsExceptionHandler.cpp b/toolkit/crashreporter/nsExceptionHandler.cpp
index 13c260840de5..e1163cada7b2 100644
--- a/toolkit/crashreporter/nsExceptionHandler.cpp
+++ b/toolkit/crashreporter/nsExceptionHandler.cpp
@@ -3047,7 +3047,7 @@ bool
 GetIDFromMinidump(nsIFile* minidump, nsAString& id)
 {
   if (minidump && NS_SUCCEEDED(minidump->GetLeafName(id))) {
-    id.Replace(id.Length() - 4, 4, NS_LITERAL_STRING(""));
+    id.ReplaceLiteral(id.Length() - 4, 4, u"");
     return true;
   }
   return false;