> [!NOTE]
> Prior to ASP.NET Core 3.0 web apps write one log of type `LogLevel.Warning` per request if the requested culture is unsupported. Logging one `LogLevel.Warning` per request can make large log files with redundant information. This behavior has been changed in ASP.NET 3.0. The `RequestLocalizationMiddleware` writes a log of type `LogLevel.Debug`, which reduces the size of production logs.