Disable interactive page after posting

So, I remember from before that it is possible to remove the message you get after posting a message during chat. For example, you all know when I click here "Send", there will come popup where I have to wait 2 seconds or so and decide if I want to get back to the forum or something like that. I don't want that pause, I want it "out of the picture". How to do so?

I am sorry if this is not the correct forum to post.

Thank you very much, my man.