src/Pure/PIDE/protocol.ML

     (fn args => List.app writeln args);
 
 val _ =
   Isabelle_Process.protocol_command "Prover.options"
     (fn [options_yxml] =>
-      Isabelle_Process.init_protocol_options (Options.decode (YXML.parse_body options_yxml)));
+      (Options.set_default (Options.decode (YXML.parse_body options_yxml));
+       Isabelle_Process.init_options_interactive ()));
 
 val _ =
   Isabelle_Process.protocol_command "Document.define_blob"
     (fn [digest, content] => Document.change_state (Document.define_blob digest content));