\relative c' \context Staff {
\grace { a'16[ f] } g1
\bar "||" % test if | and || are synced.
\grace { a16[ bes] } c1
\bar "||" % test if | and || are synced.
}
\relative c' \context Staff {
\grace { a'16[ f] } g1
\bar "||" % test if | and || are synced.
\grace { a16[ bes] } c1
\bar "||" % test if | and || are synced.
}