2.6 Manual conversions

In theory, a program like convert-ly could handle any syntax change. After all, a computer program interprets the old version and the new version, so another computer program can translate one file into another.³

However, the LilyPond project has limited resources: not all conversions are performed automatically. If convert-ly is not able to handle a syntax change, it emits a warnings like the following (from the 2.23.12 conversion rule).

Not smart enough to convert music following \fine.

Warning: \fine no longer enforces the end of the music.
If your piece has music following \fine that you want to
exclude when it is unfolded, use \volta to exclude it.
Please refer to the manual for details, and update manually.