Probem with formatting fields
The safest thing to do is to use the #attributes Form Control Attribute. You can specify a CSS class to target this element to then supply some css rules to indent these elements in your sites theme.

Similarly, you can add a class to add a line break somewhere within the widget markup to create your linebreak. Be sure to notice that the class example in the linked documentation takes a PHP array of class(es) (not a string label for the class) ... that messed me up last week for like 20 minutes.