The editor of a room has become very broad, covering more than the entire browser window and the tools are in one line. How can I regain normal size where the toolbar is on two lines and I do not have to scroll horizontally. This happens to all users in that particular room who usees the tools news, but not in other rooms. Does anyone know how I can reset the editor to normal size?

In that room you should have a look at the news items. Probably there is an item that uses a very long textline. Put an enter in so the line is shorter and the problem will be solved.