In both earlier manuscripts, the accompaniment in these bars is a repetition of the version of bars 65-66. Eventually, Chopin replaced the chords with dyads and added a touch at the beginning of bar 82. The latter was probably aimed at avoiding the stoppage of an audible rhythmic pulsation in the face of the introduction of the syncopation in the melody.
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category imprint: Differences between sources; Corrections & alterations
issues: Accompaniment changes
notation: Pitch