Changing the nickname is confusing.

It is not intuitive that my nickname is a textbox where I can type.

I was going to write a message, and accidentally wrote it in the wrong textbox and changed my name.

In HexChat when you click on your username it comes up a popup that prompts you to change your username. This seems like a more sane approach. However, I favor a popover instead of a popup/modal.

I would request there be an UI-review to discuss whether there could be a more user-friendly and intuitive way to change the nickname that is less confusing.