The chord which opens the bar in A is written without the 
before the topmost note, which is an obvious oversight. Chopin resigned from this chord, while proofreading FE (→GE,EE). The traces of its deletion – along with the arpeggio – are clearly visible in the subsequent copies of FE. Cf. bar 13.
Compare the passage in the sources »
category imprint: Differences between sources; Corrections & alterations
issues: Omission of current key accidentals, Errors of A, Authentic corrections of FE
notation: Pitch