diff --git a/planemo/galaxy/config.py b/planemo/galaxy/config.py
index a0a2a4a98..4b94e704c 100644
--- a/planemo/galaxy/config.py
+++ b/planemo/galaxy/config.py
@@ -493,7 +493,7 @@ def config_join(*args):
             migrated_tools_config=empty_tool_conf,
             test_data_dir=test_data_dir,  # TODO: make gx respect this
             shed_data_manager_config_file=shed_data_manager_config_file,
-            outputs_to_working_directory = "True",
+            outputs_to_working_directory = "True",  # this makes Galaxy's files dir RO for dockerized testing 
         ))
         _handle_container_resolution(ctx, kwds, properties)
         write_file(config_join("logging.ini"), _sub(LOGGING_TEMPLATE, template_args))