Unfortunately I can't insert the picture of how the chat of the tournament
lichess.org/tournament/0t0GLWauis looking now, but I see only one line. Only one! The last one.
I'm not sure I can use the chat properly in these circumstances ((
I also wish I could control the size of chat windows throughout Lichess. In studies it is also small. The input text field is always one line long. The chat window above that varies in size depending on the browser (or app?) being used and zoom setting.
In my browser, Ctrl - and Ctrl + decreases/increases zoom and affects the size of the chat.
It is a combination of the browser you are accessing the site on as well as the way it is set to fit the screen.
Developers are aware of this problem since the streamer battle arena but I have heard of no progress on the solution so far.