LilyPond program-reference: 3.2.14 break-alignable-interface

### 3.2.14 break-alignable-interface

Object that is aligned on a break alignment.

#### User settable properties:

> `break-align-symbols` (list)

>   A list of symbols that determine which break-aligned grobs to align this to. If the grob selected by the first symbol in the list is invisible due to break-visibility, we will align to the next grob (and so on).

This grob interface is used in the following graphical object(s): BarNumber and RehearsalMark.

#### Internals Reference