--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -3736,19 +3736,19 @@ nsDocShell::FindItemWithName(const char1
 }
 
 void
 nsDocShell::AssertOriginAttributesMatchPrivateBrowsing() {
   // Chrome docshells must not have a private browsing OriginAttribute
   // Content docshells must maintain the equality:
   // mOriginAttributes.mPrivateBrowsingId == mPrivateBrowsingId
   if (mItemType == typeChrome) {
-    MOZ_ASSERT(mOriginAttributes.mPrivateBrowsingId == 0);
+    MOZ_DIAGNOSTIC_ASSERT(mOriginAttributes.mPrivateBrowsingId == 0);
   } else {
-    MOZ_ASSERT(mOriginAttributes.mPrivateBrowsingId == mPrivateBrowsingId);
+    MOZ_DIAGNOSTIC_ASSERT(mOriginAttributes.mPrivateBrowsingId == mPrivateBrowsingId);
   }
 }
 
 nsresult
 nsDocShell::DoFindItemWithName(const char16_t* aName,
                                nsISupports* aRequestor,
                                nsIDocShellTreeItem* aOriginalRequestor,
                                nsIDocShellTreeItem** aResult)