The text turned brown at the end.. Why did this happen and what does that mean?

It doesn't mean anything, just when your message is too long it's put onto a second line, and anything on the second line is brown, not sure why this is, but it means nothing.

I hope this answers both your questions.

In older versions all of the names appeared in black without angled brackets. Your own messages appeared in brown instead.

Changes were implemented on top of the existing system. You see the first bracket in brown because somebody forgot to add an extra colour code for it, and the text on the new line doesn't keep the colour codes from the first line.

TLR: Chat is wonky.

So it keeps the bottom line correct?

Yes, only the second line.

so it's basically an error that hasn't been fixed for years ? lol

I’m pretty sure there are several things more important than just a line of text getting brown to do

It's just a simple feature which became useless years ago and since it's not very urgent to remove it, it's still there. Not much more to say.

Closing as the original question has been answered 3 weeks ago.