Change the output aspect ratio. It’s 16/9 by default, but you can also set it to automatically fit the output window aspect ratio. If this is different to the output aspect ratio, the content will be contained inside. Also there are some more handy features here.
If you set this to e.g. 2 all the textboxes will show max 2 lines in the output at the time. This is useful if you want a second live stream output to only show 2 lines at a time, while another output shows all the lines.
You can set a template to override the output style to get different styles in outputs with the same input, useful for lower thirds. The template text color will be used, unless the slide item text has multiple colors, in that case the original colors will be used!