src/Tools/solve_direct.ML

 
 val max_solutions = Unsynchronized.ref 5;
 
 val _ =
   ProofGeneral.preference_option ProofGeneral.category_tracing
-    (SOME "true")
+    NONE
     @{option auto_solve_direct}
     "auto-solve-direct"
     ("Run " ^ quote solve_directN ^ " automatically");