Dialyzer: The function call will not succeed.

:idna.encode/1 expects a charlist even though it will accept a binary string. That functionality is undocumented / not part of its typespec, so we should turn it into a charlist first. Also switch to using match?/2

lib/pleroma/user.ex:2056:call
The function call will not succeed.

:idna.encode(_host :: binary())

will never return since the success typing is:
(string()) :: string()

and the contract is
(string()) :: string()

lib/pleroma/user.ex

@@ -2053,7 +2053,8 @@ defmodule Pleroma.User do
            %{scheme: scheme, userinfo: nil, host: host}
            when not_empty_string(host) and scheme in ["http", "https"] <-
              URI.parse(value),
-           {:not_idn, true} <- {:not_idn, to_string(:idna.encode(host)) == host},
+           {:not_idn, true} <-
+             {:not_idn, match?(^host, to_string(:idna.encode(to_charlist(host))))},
            "me" <- Pleroma.Web.RelMe.maybe_put_rel_me(value, profile_urls) do
         CommonUtils.to_masto_date(NaiveDateTime.utc_now())
       else