According to us, omission of the additional quaver stem next to f
1 is a result of the Chopin proofreading of FE (→EE), which is indicated by possible traces of correction in print in this place (e.g. a slightly bigger note head of the note). Taking into account the fact that in analogous bar 130 f1 is not extended, one can come to a conclusion that Chopin could have written the fourth stem in the discussed bar by mistake.
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category imprint: Interpretations within context; Differences between sources
issues: Authentic corrections of FE
notation: Rhythm