The <appearance> element controls general graphical settings for the music's final form appearance on a printed
page of display. This includes support for line widths, definitions for note sizes, standard distances between
notation elements, and Standard Music Font Layout (SMuFL) glyphs, plus an extension element for other aspects of
appearance.
The
<appearance>
elementParent element:
<defaults>
The
<appearance>
element controls general graphical settings for the music's final form appearance on a printed page of display. This includes support for line widths, definitions for note sizes, standard distances between notation elements, and Standard Music Font Layout (SMuFL) glyphs, plus an extension element for other aspects of appearance.https://www.w3.org/2021/06/musicxml40/musicxml-reference/elements/appearance/