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kotlinlang

Anyone know how to fix this?
This declaration is experimental and its usage must be marked with '@io.ktor.util.InternalAPI' or '@UseExperimental(io.ktor.util.InternalAPI::class)'

How about annotating your declaration with `@UseExperimental(io.ktor.util.InternalAPI::class)` ?

You may also think about it : you are using a declaration that is part of the internal API of Ktor. By enforcing this annotation, the Ktor team strongly discourages using those declarations directly in your app, since internal APIs may be removed in the future without a warning.