The fifth on the 3rd beat of bars 2 and 6 in CLI is probably the original version. The c1 notes were originally absent also in FE, as in both bars Chopin added them in FEcor. Chopin hesitated in which places to put the cautionary naturals before c1, which can already be seen in FEcor, where before the triad on the 2nd beat of bar 2, a 
was written and then deleted. Eventually, FE (→EE2→EE3) has a sign before the triad on the 3rd beat of the bar, which we adopt to the main text in all analogous bars. GE1 (→GE1a) has a before the 1st triad in both bars, while in the later editions arbitrary additions were also performed in this respect.
category imprint: Differences between sources; Editorial revisions; Corrections & alterations
issues: Cautionary accidentals, Accompaniment changes, Authentic corrections of FE, Uncertain notes on ledger lines
notation: Pitch