diff --git a/src/mint-lib/test_mint_api.c b/src/mint-lib/test_mint_api.c
index 71e23f473..69a50e036 100644
--- a/src/mint-lib/test_mint_api.c
+++ b/src/mint-lib/test_mint_api.c
@@ -1999,7 +1999,7 @@ run (void *cls,
       .details.deposit.transaction_id = 2 },
 
 #if TEST_REFRESH
-
+    
     /* Test running a failing melt operation (same operation again must fail) */
     { .oc = OC_REFRESH_MELT,
       .label = "refresh-melt-failing",
@@ -2007,6 +2007,9 @@ run (void *cls,
       .details.refresh_melt.melted_coins = melt_coins_1,
       .details.refresh_melt.fresh_amounts = melt_fresh_amounts_1 },
 
+    // FIXME: also test with coin that was already melted 
+    // (signature differs from coin that was deposited...)
+
     /* *************** end of /refresh testing ************** */
 #endif