Issues : Errors of A

b. 3

composition: Op. 26 No 2, Polonaise in E♭ minor

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The overlooked in A flats restoring A and a on the 3rd beat were added in FE (→EE,GE). Similarily in the subsequent instances of this bar – bars 51, 107 & 155 (in bar 155 correction omitted in FE).

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , Errors of A , Authentic corrections of FE

b. 3

composition: Op. 25 No 8, Etude in D♭ major

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In A (→GE1), FE and EE there is no  returning f2 in the penultimate sixth. This patent error was noticed only in GE2 (→GE3) on the occasion of a thorough revision of accidentals – cf. the notes concerning the natural and flat before the previous sixth. 

category imprint: Interpretations within context; Differences between sources

issues: Errors in FE , Errors in EE , Omissions to cancel alteration , Errors in GE , GE revisions , Errors of A

b. 3-4

composition: WN 37, Lento con gran espressione

c1 repeated in A1

c1 tied in CJ, CK (→CB) & EL

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The missing tie of c1 is probably Chopin's oversight in A1, hence we consider it acceptable to add it in the text of A1.

category imprint: Differences between sources

issues: Errors of A

b. 3

composition: Op. 28 No. 22, Prelude in G minor

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In A (→FE) there is no  raising f1 to f1. The manifest inadvertence was rectified in FC (→GE) and EE.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors of A , Fontana's revisions , Errors repeated in FE

b. 3

composition: Op. 28 No. 20, Prelude in C minor

e1 in A (literal reading→FE,FCGE), AB & EE2

e1 in ACh, CGS, EE1 & FES

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According to us, it is much more likely that the missing  restoring e1, which would result in e1 at the end of the bar, is one of numerous such oversights of Chopin – see, e.g. the note to b. 8 and 12 as well as to the Prelude No. 7 in A Major, b. 13 or No. 18 in F Minor, b. 8. Therefore, we assume that the flats entered or added in ACh, CGS and FES define or restore the only correct text, which we adopt as the main one. However, the version with e1 has a consistent place in the history of music, e.g. as the theme of variations of Feruccio Busoni (BV 213a) and of Sergei Rachmaninoff (Op. 22).
The double revision in EE is noteworthy – first a  was added in EE1 and then it was removed in EE2.  

category imprint: Differences between sources

issues: Annotations in teaching copies , EE revisions , Omissions to cancel alteration , Errors of A , Annotations in FES