MuseScore does not support footnotes
MuseScore doesn't have, the possibility to include footnotes attached to a note. Footnotes are important in annotated scores, where comments on style, technique, historical data, etc. are necessary. A footnote should be placed at the bottom of the page, immediately above the footer, and should always be on the same page as the note which it is attached to. If for any reason after an edit the measure containing such note happened to jump to another page, the footnote should move along to the new page. Ideally, footnotes should suppoprt images.
One property of footnotes could be autonumbering according to several optional stlyles: arabic numbers, roman numbers, low case letters, capital letters or some type of symbols, and would be enclosed between brackets (or another custom method). Parts should inherit the footnotes originated in the part but visibility should be optional.
Comments
Came up again in #302979: Add footnote capability and earlier on https://musescore.org/en/node/286481