What does "Opening in BLOCKING MODE" mean?

I’m seeing this message in my console and I’m not sure what it means:


What does it mean?


can you specify a bit, under what circumstances this happens?
Just guessing, this means that it will open what ever you are on the same thread as the main app, thus while loading the app will not respond as it is working on loading. for this to not happen you would need to use an asynchronous loading method. But I can not really say much more or advice if you dont provide specifics.