Steps to replicate the issue (include links if applicable):

• edit any page with dark mode enabled using VisualEditor
• open the 'add musical notation' dialog
• type in any lilypond code, e.g.:

\relative { \clef bass \key f \major \time 4/4 r4 c d f f2. f4 f c8 c8( c4) c bes bes bes bes bes bes8 bes8( bes4) } \addlyrics { Pro -- bier’s mal mit Ge -- müt -- lich -- keit, mit Ru -- he und Ge -- müt -- lich -- keit }

What happens?:
the preview on top of the edit box is missing inversion for dark mode and looks odd

What should have happened instead?:
skin-invert should have been added to the preview image

Software version (on Special:Version page; skip for WMF-hosted wikis like Wikipedia):

Other information (browser name/version, screenshots, etc.):