Show hint if no server connection is available
I was recently made aware that the text input field is disabled when no server connection is available. I have not had the slightest idea that this was on purpose. I had previously believed it was just some UI bug and had my own ritual (reminiscent of #11783) of minimizing and re-opening gajim to "make it work again".
I believe adding a brief notification of some kind, informing the user that no connection is available, would go a long way for intuitive UX.
I could imagine a status message directly in the disabled input field, or something similar to the loading indicator for transmitting files.