I know about in-game dialogues but their text is being typed out and it seems you can’t use HTML (even for line breaks), and I’m more for something like in TD, when you join the game you can instantly see something like this:
The welcome to TD was written before dialogues were available. There is a restricted (and deprecated?) function called show custom modal to player. The modal allowed html to be entered but the risk with allowing raw html is that you could redirect to malware or offensive content.
I agree with the points you are making so I’ll suggest the following, we’ll have to wait to hear from m0dE if he agrees with anything.
we should accept \r\n or \n or <br> just some kind of way to make a newline.
if the letter print speed is 0 (or negative just some convention) for dialogs the text should just appear at once.