diff --git a/steam-runtime-tools/json-utils.c b/steam-runtime-tools/json-utils.c
index c9bdafe7fdef185ad5994a03b3775254f85041dc..a80f2748a3051d54cf9ba5379c81d370581c31c9 100644
--- a/steam-runtime-tools/json-utils.c
+++ b/steam-runtime-tools/json-utils.c
@@ -302,7 +302,12 @@ _srt_json_builder_add_strv_value (JsonBuilder *builder,
       json_builder_set_member_name (builder, array_name);
       json_builder_begin_array (builder);
       for (i = 0; values != NULL && values[i] != NULL; i++)
-        json_builder_add_string_value (builder, values[i]);
+        {
+          g_autofree gchar *valid = NULL;
+
+          valid = g_utf8_make_valid (values[i], -1);
+          json_builder_add_string_value (builder, valid);
+        }
       json_builder_end_array (builder);
     }
 }