The sources are lacking in the accidental before the 2nd played note of the run. It must be Chopin's mistake (one of the most frequent ones – oversight of an alteration's cancellation), since a2 would have suggested a turn towards B
major (G minor), and not F minor, whose dominant we are about to hear. Due to the absence of this accidental, a2 should also be in the ending of the run.
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category imprint: Interpretations within context; Editorial revisions
issues: Omissions to cancel alteration, Errors repeated in GE, Errors repeated in EE
notation: Pitch